looking for advice
I guess I'm needing to vent and found this site after googling for some advice...let me give some history into my relationship...I have been dating a guy for almost a year, we both came from similar relationships, both having been divorced, the only difference being he has a 28 month old son. The relationship is fantastic between him and I, and between his son and I was great up until this weekend. We live together, and have him every other weekend, then one day/night every week. Previously, his son absolutely adored me. He is an incredibly affection and loving little boy. Whenever we were anywhere, whether it be around family or by ourselves there was absolutely no doubt he loved me and loved being around me. I picked him up at the beginning of the weekend and we had a great day while his dad was at work. The following morning, it was like a switch flipped, he would act as though he was upset with me, not wanting to be near me, if I walked into the room he would glare at me and/or hide his face. It got to the point where he would start crying and cling to his father. We tried ignoring it, asking him what was wrong and it got to the point where I felt like I shouldn't even be in the same area as him. This behavior continued on and off for the rest of the weekend. Again yesterday his father had to work, so I was left with him. I was scared to death he wouldn't want anything to do with me, but we had an OK day. There were a few occurances where I started getting looks, but I tried to ignore it in a positive way, keep my composure and not take it personal and just act how I normally would and have in times past. I understand kids go through mood swings, but it is so hard to understand because he can't communicate what is going on inside his head. Has anyone experienced anything like this, or have any advice for me? I am hoping it is a phase, I just am having a hard time understanding this sudden shift, especially when I have not done anything, or nothing has changed between us. I am supposed to spend time with him later this week, and I am so fearful we will have this happen again. Ugh, thanks for listening...or reading rather!!! 
Just sounds like the terrible
Just sounds like the terrible twos...Be patient at this age they change daily.
I honestly considered that,
I honestly considered that, but its hard to imagine he'd be capable of holding a grudge or being told anything by her and holding onto it. We have him all day Thursday through Friday morning, unless its a weekend to stay with us, then we keep him through Sunday afternoon.
We all know she isn't happy with the situation, none of us are, but the times I've met her she's been friendly, whether genuine or not, and I've been nothing but nice to her. Its a difficult situation for everyone, and as niave as I can be thinking we can get along I still recognize why she's upset. I'm sure I would be too...
We will see what happens! Thank you all for your responses, it made me feel much better being able to share it with people who can relate with me and my situation. He does great trying, but he's even said he can't fully understand what I go through.
Just keep things
Just keep things lighthearted. Don't take it personally. When our youngest BD was that age, she'd switch back and forth between who was her favorite, me or DH. I honestly don't think he's old enough to be consciously singling you out because you're not his mommy or daddy. Most kids that age like anyone who's paying attention to them. Just keep doing what you're doing.
I have quite a bit of
I have quite a bit of experience working with toddler's and twos, from working in a daycare setting for numerous years. I just had never experienced this specific behavior, or I should say I viewed it differently since I wasn't seeing the child as "mine" so to say. He is definately starting to test boundaries, enjoying the responses he is getting and showing frustration when it comes to expressing his emotions. As far as SO, we have talked a lot about discipline, reactions, and setting boundaries with his behavior. I've explained to him from my own experiences, kids LOVE reactions, that is the basis for most of their behaviors. He is very open, supportive, and I honestly feel like we are a team and he asks my advice and opinions. He is still learning, and figuring out how to handle certain situations, but he has stepped up and puts his foot down in a positive way rather then letting the little guy run the show. Now, with BM I'm not so sure, I feel like she lets him run the show.
Thank you so much for the discussion! You guys have helped tremendously!!!!!