I KNOW THIS IS LONG BUT PLEASE READ ANY ADVICE WOULD BE HELPFUL!!

My husband and I have been together for four years now and we are also married. 2 weeks after we got together his Baby's mother started harrassing me and texting me that she was pregnant with his child and he's this, that and the 3rd and it has continued for the last 4 years now! She doesn't stop and now that we are married it's getting worse. She thinks he is going to leave me and go back to her. She was a "friend" who said she was on birth control and wasn't and ended up pregnant. They didn't even know the baby's was my husbands until a paternity test proved otherwise. My husband has taken full responisiblity of his son but it's hard when she continues to keep him from us and brainwashs the child. He's almost 4 and doesn't talk because she continuously tells him to shut up and doesn teach him anything. He is a trophy child for her just to say this is my husbands son. my husband pays 700 a month for one child and she makes 5 an hour more than him!! She doesn't even use the money for the child!! He comes to our house every weekend (now that we have a court order)with the same outfit that's too small, he even came in girls clothes once! I've called childen and youth several times and they do nothing. She will call my husband in the middle of the night just to tell him all the horrible things he's done (flooded the bathroom bc she wasn't paying attention, almost caught the house on fire bc he was playing with candles when she wasn't paying attention, ect.) She admits to my husband that she cn't handle or control him and she doesnt know what to do but she would never admit it in court! My husband recently entered the military to get away from her and to have a better life for us and she did everything she could to stop him from leaving! She plans to take him for all the money she can get and I know she'll get it even though she doesn't even pay attention to the poor child!! I feel so bad when he's not with us bc i'm scarred of what will happen to him! I love my step son tremendously but i can't deal with "her" all the time!! I'm going insane. Now that my husband has left for the military she filed to sue him for more child suppost AGAIN! I am his power of attorney and will be taking his place which will infuriate her to no end. i don't even have visitation right to see my step son due to her attorney telling the judge there is too much annamosity between her and I (due to the fact I had her arresed for the continuous harrasment) even though it has nothing to do with the child the judge granted it and I have no visitation with him while my husband is away. My husband's mother does get visitation but only when the BM sees fit. So my step son goes to my mother in laws every sun for about 8 hrs. which is less than 2 days a month and we still continue to pay 700!! I love my stepson but i don't even want to go see him sometimes because i just get so upset and frustraed with his mother and the things she does and doesn't do for him!! Does this make me a bad parent?? I'm just tired of being a part time parent!! My husband and I are palnning on having a child next year and I know things will only get worse from there!! Again I do love my step son but it hurts to see him to know that anything i try to do for that little bit of time will be reversed as soon as he goes back to his BM. She constantly curses in front of him and calls me a "Cunt" in front of him. She puts all kinds of nasty things about my husband and I on facebook but I can't prove it bc i have no access to see it. She steals pictures of my husband and stepson off my page and claims them as her own, she even tells people that they are still together! I'm just at my with end and i don't know what to do!!! Please help