I think my best friend likes my girlfriend? What do I do?

[Sadique]

This person has been my best friend ever since we was three years old

But recently I had the thought that he likes my girlfriend

He use to think she was ugly, didn't like when I spoke to her , and he told me I can find a better girlfriend

But 1 night I was video chatting with her and out of no where, he told me he never said she was ugly or thought she was ugly when me and my girlfriend stopped video chatting

Then 1 day I called him and in the middle of our conversation he told me he was looking at my girlfriend's facebook profile
And my heart dropped
I didnt say anything because he is in his own serious relationship
Then later on that night my girlfriend told me he added her on Facebook
Then I was convinced that he likes her

I already have a low self a steam and think that im ugly and im scared that 1 day she might like him back
I been stressed out about this for a week now
I didnt eat in three days
I cant sleep and I don't wanna talk to my family about it