What do I need to do at this point in the game here?

My girlfriend of over 8 years has been extra difficult the last few months. She is on my and my children for everything. She speaks under her breath, she is ultra demanding, and makes us all feel like ****. She is ok when she comes to my home, but I moved in with her and when my kids are over for the shared weekends she is on the for everything. Yes, she cooks, cleans and makes the home look great, but if we spill something, and break something, what out. She tells me that I don't care enough about her when the kids are over, yet when I go to put my arms around her, she pushes away. She claims that she loves me, but the vibe I get is something very different. I am taking care of sick parents in NYC and she has been alonw for much of the summer. I have asked her to come see me, she does, and we go to dinner. She cant come during the week due to work the next day, but when her friends call, she goes out any time. I pick my kids up in NJ and drve back to NYC. She asks if it is ok if she does not come,tells me she is tired, misses me, loves me, but then goes out with a friend for a bite to eat, etc. I come home to her with my boys and the moment I get there, the crap starts. Its constant bickering. The other day she got on me and my boys so bad that I lost it and hit the wall. She called the police. It ended as soon as they arrived but my boys and I dont need the added drama. I have been there for her. I celebrated her birthday with roses, a gift and a cake with me kids, and she could not care less. I have two options. Stay with her, and deal with these crazy mood swings, or remain in NYC, turn my place into a funky loft, and date. I can have a great life, meet new women, and find the right one for me, ending it with her, and this constant battle. I dont want to go, but she drove me away. I can't fake it, and dont feel connected to her anymore. she may feel the same way even with the I love you emails and such. I cant let my life turn into some drama series with fights day and night. I can not tell you how many times she told me to get the hell out of her home, my kids to, only to stop me on the way out. She has great qualities, but I cant live like this. I want to be happy. I am a giver, and she has has very rough relationships in the past, where men would not do anything for her, or go anywhere with her. She was alone even on new years eve. I give her all of me, and I want to be a happy family, but the more I do the less she seems to care. when I am a prick she seems to respond better than when I am mr nice guy..do I stay in NYC and live the life of dater and romantic man, or do I stay with her and try to get her to see my point of view. I have tried the latter many time before, but got nowhere..HELP ME OUT !!!!