How can I get back on him?

I use to have a friend... he was the best person I had ever meet, I thought I can share everything with him
But one day I had shared about my crush... since then his behaviour is changed...
I am trying to make the things up...
And now in doing so, I think I had fallen for him!
And now his mr. Attitude mode is on... he is roming with a girl which was her school best friend, and believe me the chemistry between the two hurts...
And now clearly he has stopped talking with me... and whenever I does tend to shoot me away by ignoring me
😭😭... I don't know what should be don't in such kinda situation
How can I get back on him?
Add Opinion