Confused with my marriage and husband makes me feel guility because of it. Our relationship started out rocky?

but we could never part. He was married, and I had no clue up until we moved in together. I was 20/or 21 still very young when we met. Though I know I should have left so he could figure everything out, he wouldn't leave me alone and with that I couldn't let go. That is how it is to this day. Over the course of our relationship dating 2 years, married 5, he has did stuff to break my trust each time hurting me more and more and again, when I try to leave him, he begs me to stay, to give him a chance, that he will change. He didn't divorce his ex until after we lived together 1.5 years...and after I got pregnant. He even said, I dont want to leave a for sure thing when i dont know if you will stay with me (afraid of being alone?) He would talk to her almost daily from what I found out. They went on a 10 day cruise together while we were living together but told me he was away with military work and after she told me 9months later, his excuse was, they had already purchased the cruise before he and i met and that he had been with her for 10 years, and only with me 3 months. While I understand his reasoning, I didn't ask for him to approach me with no wedding ring on in the first place. That was almost 7 years ago, and it still haunts me. Along with the numerous things that he has done. Last year, his best friends wife told me that my husband cheated on me with our nanny (a yr after it happened) another friend has confirmed it also. I even called the nanny and she confirmed it (she was a bit crazy) but the stories add up. My husband denies it. But as he denies it he says "you probably were cheating around that time". I wasn't! I had a new, high demanding military related job which I worked very hard to try to be successful. Yes! I probably didn't cater to his needs as I usually did but I was stressed with the job (because he is money hungry) with a new baby, a 2 year old, I didnt want to be a failure. Every time I have tried to leave my husband for things like these, we talk, and then he immediately tries to make up (with having and going on with our life and him acting better to me for a week or less).... without giving me time to heal. Then he tries to make me feel quilty because he has no family and left his ex wife...he says things like, you just go, and I'll just be myself, go back to your old life with your old friends that is still doing the same thing, but thats not what I want. I'm 5 hours away from my family and old friends...and I dont have friends where we live now, and I'm now jobless. On top of the past betrayal, he is grumpy, always complaining, getting loud, over even the littlest things, he says its not me but the kids stress him, but he does get frustrated wtih me... always rushing me, asking me why I did something... he is a great dad (minus his frustrations and anger), and he shows me attention when he wants it in return, he helps around the house more than most,...and he reminds me that I would not find another man to do the things he does around the house and with the kids. While he is probably right, what does other men have to do with what I want in a relationship. He says that marriage isnt always fairytale, just another comment he makes to make me feel like a child, I know its not a fairytale, but it can be close to what you want if you are with the right person, i believe. Recently I brought up the nanny story (because it never resolved and because I cant help it, I'm hurt) and I told him how it hurts that he needs to come in from work and take a xanax to be around his family, or take 1 before a family outting. The kids even have anxiety....they get so frustrated so quickly...possibly picking up on his attitude. And because my husband has an attitude all the time, I'm gotten cold to him...and he cant understand that. Just a week ago he got put on zoloft for depression and because I say I'm done with our marriage because of his 7 year of action, he asks me to just give him a chance that he just started medicine...I want to in my heart.. but my head is telling me no....nothing will change...and my emotions are battered...but he cant see why i need time!! Thats all I've asked, but he walks around the home pouting, and trying to talk to me about takin him back, trying to kiss my, trying to have with me...because he knows if I allow him, then he would think everything is ok...treat me like a princess for a week and then be back to his normal self.... Do I owe him another chance and forget my feelings once again??? He has no family and throws that up in my face and how he grew up... being the way he is... I didnt grow up that great either.. my mother always yelled at me everyday, anger issues, she yells at my dad just a very unhappy woman.. I couldnt take her complaining and yelling so I left home as soon as I could...but I feel like i'm in the same dealing with how my husband talks to me...but he is my best friend...