Feeling Insecure

Hello,

I've never posted here before, so I'm not sure what to expect. I've been in a long distance relationship with my girlfriend for about four years now. Next September I am going to be moving near her, hopefully. I say hopefully because my physical health isn't the best. The goal is to get better before I move there.

The thing is, I'm not a very insecure person. I used to be, but it isn't as bad as it used to be. However, it hasn't been easy lately. I look at pictures of her and listen to her voice and I wonder why she chose me. She is incredibly beautiful. I am attractive, but I don't think I'm attractive enough to be with her. When I say that she's the most beautiful girl I've ever seen, I mean it. She is an incredible person, too. I'm terrified that she'll see right through me and will realize that I'm not good enough for her. Actually, I believe that I can become more than good enough for her. Let me rephrase this ... I am scared that she'll decide my mental health is too much for her to deal with. I'm terrified that everyone doubts me when I say that I want to get better. She is such a sweet person. Deep down I know that she just wants me to get better so that I'll be happy and she truly does love me, but I am feeling so insecure. She's too beautiful for anyone, honestly. She's so gorgeous that she makes me sit there and think about life. It's the equivalent of too seeing a natural phenomenon.

How do I stop feeling so insecure?