Help

I am a part of a group in which I was added 10 months ago. I have created lots of memories with them. However I constantly feel that I am not interesting enough for everyone there. Whenever we all are sitting together I feel like even if I disapper it won't affect much to anyone. Also there's someone who i find attractive so lately I've been trying to get her attention the most and since I don't get that much I compare myself with the rest of the people in the group who are on good terms with her and i question my worth. I was also on good terms with her but since I compare myself so much with others I started avoiding her which has resulted in me feeling like I am no longer important to her. How do I detach myself from this person and stop myself from continuously comparing with others.