I'm having some problems, Can you guys give me advice??

Well first of all, I have 2 kids with my ex-boyfriend. He has a girlfriend right! Well, shes getting on my nerves. My ex came over to see our kids and we talked about things. I ask him how him and his girl are doing and he told me she is bitching alot. I was like why whats going on now. He told me that when they fight, its about me. I was like oh really why does it always have to be about me, its all the time. She wants to kick my a$$ because I told her to mind her own business. I don't think she doesn't trust him because shes always going through his e-mails and his phone. Last week I emailed him to send him pictures of our kids because I promised him When ever he comes to see our kids he gets pictures of our kids, well, anyways so I did and I knew she was gonna go through his email and I told her to mind her own business and stop going through his email. My ex told her off about it and shes pissed off. I think she is jealous because she can't have the same thing as I do with him. She can't have kids!! Why does it have to be all about me?? I guess I don't understand why?I'm having some problems, Can you guys give me advice??
Sometimes when people are in a relationship they feel they share everything. that's probably what she thinks. And it's just a picture of your kids I'm sure she's already seen them. So I guess in the future if you want to make something private call him up. Don't leave anything that she can look over