I'm happy but I feel so worried?

A few months ago I was in a really bad place. I had no money, no job and no boyfriend. I envied my friends because they all seemed to have everything I wanted. This pass month I got a new job that I love and I've started seeing someone who seems to really care about me and makes me happy. But I'm so terrified of losing everything again that I just can't relax? Everything is fine, I have nothing to feel sad about but I can't help feeling emotional at the thought of going back to that bad place. I just want to be able to focus on the present and not worry about the future. It seems every time I start feeling happy, something happens and it all crashes and burns. I'm scared of it happening again. Am I worrying over nothing and how do I stop?