Real bad jealousy and anxiety

Ok ladies so I have been having this real bad jealousy issue every time I see a pregnant woman some times In get so mad a jealious that I think about punching kicking and tripping just random females because they are pregnant now don't get me wrong they are just thoughts and I have never acred on them I mean I know and clearly understand that it's not a good thing to feel like this. I just wish I had the proper help to not feel this way inside and some times I cry myself to sleep because I want to have a child so bad and the killing part is every time I take a pregnancy test and I find out the I'm not pregnant I just cry. My fiance told me that it is okay that even if I do not get pregnant he's fine with adopting but the thing is I'm not trying with it I want to be able to feel my child inside of me is that crazy. I mean it may be disappointing him but now I just kind of want to give up that it will never happen for me I'm just tired of trying so hard so times I just sit in a corner and talk to God and ask him if he dislike me for some reason. Is there something in my life that I have done to disappoint him and I know for a fact that I will be a dam good mother as much and I take care and provide for my step daughter and other children and the Crazy thing is sometimes I get jealous of her and I told him that and he asked me why and I told him because I don't think that I will ever have a child of my own. I think I'm going crazy I never see my self ever hurting a child physcilay Lily and some times I be happy when my step daughter tells her dY she is ready to go home but most of the time I don't want my little angle to leave at all because I love her so much