HELP : why am I so JEALOUS?!

I find myself to be ridiculously jealous and I hate it! To the extreme of if a lady has a low cut top on or tight pants on it makes my stomach hurt to think that my husband might be looking or thinking about her. If someone references sex it makes me mad because I think my husband might be thinking about the girl in the reference. Whether it’s on TV, real life, I am constantly jealous and I HATE IT. I wish I could just get over it. What do I do?!