Trying to get pregnant.

Me and my fiance have been trying to get pregnant for a year now. I finally did get pregnant back in April 2015. But ended up having a miscarriage. And I of course blame myself for it. I've never handled stress very well. But we still haven't given up on trying. I think the part that gets to me the most is that he already has two kids. And all it took for him to have his kids was two drunken nights. And he barley gets to even see his children. All I want to do is make him happy. And I want him to be able to have a child he can watch grow up and that he can spend as much time as he wants with. I just feel like I'm dissapointing him.And it's taken me over a year to get pregnant. And that makes me feel like it's my fault that we can't have a baby of our own.