You sound like you basically like him but don't have warm fuzzies about him.  You also sound like you want the best for him.  All this is ok.  My only concern is your DH's wanting you to love him, that's unrealistic.  Read around on here and you will see this same situation in other homes.

I'm a 76yo SM of 3 SKs.  My feelings about each varied and still vary, that's normal human nature.  I basically liked them and wanted the best for them, like you.  It "took" with OSS, he moved in and felt like my own son.  YSS moved in and we have always had an arms-length relationship. That love feeling just isnt there for him like it is for OSS.  Like you, I thought he was over-indulged and was the favorite of both parents.  He isnt/ wasn't a bad person, just not my type.

All this is just normal human relations.  As long as you are polite and take care of him, that's th e most DH can expect.  Good luck!

Your DH has fallen into the trap of thinking that just because you are married to him, you should automatically just absorb and take on his feelings about his son. Like you aren't your own person with your own unique experience and feelings. And your experience with his son is very, very different from his. You aren't biologically related to him. You don't remember him as a cute, helpless baby. You see him for who he is, a 10-year-old with some annoying behaviors.

This is a very selfish way for bioparents to think. Looking back i think i felt this way on some level about my own kids, but age and experience showed me that no other person in the world will accept as many faults in kids as their own parents and put up with as much bullsh!t just to be in the presence of their smiling faces. I can almost guarantee that if you had a prior relationship child, your DH would be more annoyed than you by certain behaviors, especially if he came into the child's life much past infancy. Also, 10 is a very annoying age for boys and the baby talk thing in a child almost old enough to be in junior high is nauseating to anyone but bioparents who want to keep remembering them as actual babies. 

Hey OP, does your husband love your nieces and nephews like you do? Or is that "different"? 

It's easier said then done but continuing disengagement ,

being respectful and polite to SS. Don't let your husband guilt trip you. I've know my skids since they were 6ish and are now older teens. I like them and think of them but I don't feel the same away about them as my nieces/nephews. 
 

If you don't like confrontation just change the subject when your husband goes on tirades. It's not your fault he is creating an unlikeable human. 

Good convo here for sure.  I have a 10YO SD and she too thinks that "baby talk" is a thing.  It annoys everyone no matter who it is.  Even her BioDad hates it and comments on it while he is picking her up if she decides to do it then.

The "no consequences" thing doesn't work.  You take all their shit away and lock them in a closet until they behave or get it.  Her "no consequences" life before I entered the picture is the reason why she still thinks she can do it.  I'm the only one in the house besides her 15YO SB that won't stand for her shit.  And she knows it and hates it, but it's hers to fix.  I believe that me telling her over and over that she doesn't affect me and I won't stand for her shit will eventually help.  The problem is always going to be that she will run to her mother or BioDad and then there ends up being a distrust towards me no matter what it was that occurred.

I don't want to discourage you, and by no means does my story mean that yours will turn out the same. Every indvidual is difffrent and so responses and behavious are different. 

From my experience, (huband with three kids from previou relationships, and two children together), when you try to set a rule, and your husband doesn't have your back. It's going to be an issue. You are goiing to resent your husband for this eventually. I'm going to focus on relating my story to yours so you get where I'm coming from. 

My husnband has a now 17 year old son. Lives with us full time (all kids do). My rules, since we married, were do your dishes after you eat, and help with atleast 1 chore a day. If he doesn't, friends or girlfriend can't come over. Mind you, his son is a straight A student, works, and is bright. All these years, he has never followed my simple rules, and i complain to my husband. He didn't help today, so no girlftiend can't come. Husband: i told him she could come, next time he doesn't help then he will be punished. It's been almost 7 years, and my husbands answer is always next time. It is extremely frustrating, and humiliating. My husband allowed for his kids to disrespect me in a sense because he doesnt' back me up. My husband and I are now going through a divorce.

My point in telling you this is, if your husband wont have your back in regards to rules or simple corrective behavior, the son won't respect you. The father is allowing it. Eventually, you will greatly resent your husband for it. If it's early on enough you can try to talk to your husband (it didn't work for me, but like i said we are all different). 

I really hope that you can resolve this issue together, and be able to reach and stick to an understanding. I wish the best for you, i really do! The step parent journey is an extremely difficult one. A heartbreaking one, but hopefully your story is different. 

He wants what he did not have with BM.   You are bursting his bubble,   You have to respect SS, as SS has to respect you.  You don't or can't love him just because he's DH child.   That not your problem.  Your are the third wheel !!  
 

All SP are the third wheel 

Your feelings are normal. Your SS lives in your home, yet, he is not being raised in a way that reflects your values. As the stepparent, you are expected to put those values aside in your own home, which no other adult would be expected to do.

You really have a problem with your DH. He is getting defensive likely because he feels bad about the divorce or knows in his heart that guilty parenting doesn't work, but it's the easier option. I also agree with the post above about the happy family. Your DH needs to let that go and also to partner with you as people in charge I'd your household, instead of expecting you to cater to his son. He's there 50/50, so he needs to become part of your household, which means he needs to be taught and expected to behave in a way that reflects the values in your home. It seems like your DH hasn't bought into your values or that you two don't have shared values and that can cause major problems.

You feel like a bad person because your husband is trying to guilt you about your feelings.  He needs to get over it.  SS isn't your kid.  You're not required to love or even like him.  Treat him kindly, yes, but that's it.  It sounds like they are raising a child that isn't very likeable so why would you like him or want to be around him?  If SS doesn't like you it's probably because you're not letting him run over you like he does everyone else.  My SS told dh once that he didn't like me too, that I was mean.  I didn't care.  I was not going to allow him to run over me like he did every other female in his life.  If I was so awful, he could leave as far as I was concerned.  And my dh did discipline SS, and did back me up when I disciplined.   

It very confusing because Thier is an expectation that now that you are in a "motherly role" you should just naturally be like a mother.

But that is a false reality. We didn't birth or participate in raising these kids. They do not share our genetics. They never bonded with us. They have 2 people who they already view as parents. 

Just as it is wrong to try and force a child to love  someone, it is equally as wrong to make an adult love someone. Relationships happen naturally, and they are all different. Your goals for each relationship have to be realistic and based on compatibility. 

I feel that in a SP situation, the most realistic goal is mutual respect. If it grows to become more than that, good if not that's okay too. 

I'm my situation I started off liking OSD and enjoyed spending time with her. Over time that changed, we no longer had a mutual respect. She stopped respecting my rules and boundaries and I stopped wanting to have anything to do with her because I do keep people in my circle that do not treat me with respect. So now our relationship is just civil politeness and I keep her at a distance.

YSD was extremely behavioral when we first met. Exhausting and always testing boundaries. Over time she started to show me respect because she liked that I was consistent and wouldn't let her walk all over me. Basically I earned her respect. Now we are very close and continue to grow closer as time goes on. I like her a person and think she is spunky but with a good heart.