My DH and I just got married in December of 2017 but we have been together since 2012.

The situation between my DH and my SD's BM is that they met prior to college, dated a year and split and she found out she was pregnant. She comes from a well off home but she has been in trouble with the law since SD has been 4. Stealing medications, writing bad checks, drug use. Because of this, BM and SD live with their well-to-do BM's parents (SD's grandparents or GP). My DH and SD's GP's split custody of her with them holding guardianship.

So because I have never been in a situation like this before I was quick to make sure I wasn't trying to over step my boundaries, getting on to her or reprimanding in any way. She was 4 getting ready to turn 5 and we had so much fun together. We would play all the time, make cookies, watch her favorite TV shows. I will say that I could tell immediately that my DH was really over compensating because he doesn't have her all the time. Her BMGP's (biological mother's parent) do the same because she is their only granddaughter and I'm sure they are sad their daughter is such a mess. Needless to say...

Slowly as she got older though she changed. She stopped talking to me or acknowledging me basically. She does all these things still and she's about to be 12.. first it just hurt me but now I am just fed up all the time. A few things she does to let me know she isn't fond of me is

-she doesn't acknowledge me or say hi at all when I say it to her

-she doesn't talk to me AT ALL unless I basically make her. She would go the whole day with us and not speak to me if I let it go. 

-when we are home and I get up from the couch she will purposely take my spot by my DH or if there is only one spot by him she will be sure to sit there and not get up for anything.

-she pretty much won't stay in the room with me. If he gets up, she follows him..up his butt constantly. 

-she will never say thank you to me, only acts like I owe it to her.

-she is constantly just staring at me and when I make eye contact back she just gives me the dead stare.

-she will literally HIDE in the corner outside a room me and my DH are in and just watch us like she can't enter the room or she isn't allowed. WTF?

-she never shares anything with me, she will only share it with my DH and I watch as they snack together and third wheel me..all the time. But I'm supposed to be the adult who shares with her? He doesn't even say anything such as "Why don't you ask your SM if she would also like some?" I get nothing. But if I have something and offer it just to him I get "Well why aren't you offering any to SD?"

When we got married, as I'm walking down the aisle I see her sitting in the front row with DH's side of the family and she is bawling. I think to myself "tears of joy?"...no. She heard my DH's vows and realizes that he loves me and she loses it. I truly think she thought I was just some bystander living in HER father's home and eventually I would be gone. 

I get she thinks I'm taking her father maybe or what have you but what baffles me is this is a 6 year reversal. How did we go from being so close to her blatantly disliking me? If anything we should be closer..how the hell did this happen?

My problems now are: that my DH, though we have talked about it doesn't seem to mind the obvious friction and when someone treats me bad for no reason I am done. I cannot find it in my heart to like this girl anymore. She is mean, spiteful and petty. I feel absolutely awful but I daresay I despise/hate her right now. 

I keep telling myself that this age is hard but she is a very intelligent, precocious child and I know she knows what she is doing which makes it harder. I live for when she isn't here. But disengaging has done nothing but make me feel like a 3rd wheel in my own home because he doesn't care and if he doesn't, she doesn't either.

I just needed to cry and tell someone.