Broken... Why???

I feel so angry and irritated all the time. And I hate to say it but I really blame my husband. A lot of this anger comes from the things he has done to me. He left for Iraq and while he was there he was cheating on me... I don't see how he loved me enough to marry me but not enough to stay faithful... I told myself that it happens all the time and to a lot of women whose married to a military man... But what got me and the way I found out way because he kept doing it after he got home... and he said it was because he didn't know what he wanted when he got back... Did seeing me again and spending time with me again not help him realize that I was what he wanted??? He said I was what he wanted and that he wouldn't do it again... I found out later that he didn't not only stop but he was also doing it on his phone... Does he still not know what he wants??? Was me being pregnant with his child not enough for him to want to change??? And considering he was using his phone it wasn't just over the internet it was through phone and texting... Some of them where females he actually met... He said he would stop and he wants to be with me... I asked him what was wrong with me, what do they have that I don't, what is it that they are doing that I am not... and every time it's the same thing... There's nothing wrong with me, they don't have anything I don't, they aren't doing anything I'm not... So I am then left with the question of why??? So I try to forgive him and try to move on and try not to bring it up but then I find out again that he is betraying me with women on the internet all via phone... and most of these times I find out in multiple times in a big period of time... and then it seems as though he quit... but every time... He is still sharing himself with females all over the internet and for all I know all over the world... I am so angry and so tired... I don't know why he does it and I don't know why he feels like he can keep doing this to me... I can't seem to get over this anymore or again... I never should've had to get over it to begin with. I even get angry with my kids and yell more than usual and more than I should  but it's because the littlest thing goes wrong and I freak out, become angry, and start screaming. I don't know what else to do. I feel stuck and I feel hurt, angry, alone, and ashamed of myself because I am not good enough. Someday I am going to be good enough and I'm going to be good enough not only to and for me but to and for my children...My children and I both deserve more than dishonest and hurtful... Someday we will be happy... I just wish it was sooner... I want the happily ever after... and it breaks my heart to know that I am most likely not going to get it where I am at... I don't even know how he can prove himself to me or earn my trust back because every time he has he has betrayed me, ripped out my heart, and said F*CK YOU!!! I'm so hurt I feel paralyzed and only strong enough to hold back the tears and fake it for everyone... I don't know what to do when I gave him my all and have nothing... I don't even have anything left give...