Getting over my best friend

So my best friend is a boy, and I think I’m in love with him. But he’s in love with my other best friend. I’ve likes i for nearly a year and a half but I never said anything until he figured it out for himself, but that was only about 6 months ago and by that time he had kissed my other friend, which killed me. He dosent have any feelings for me and that was fine.

But I started to date another boy and him and my friend started to date and I ended up ending things with the other boy because I realised that he wasn’t what I wanted, my best friend was, and my girl best friend ended things with my boy best friend, and I thought I was over him, but I’m not and every time he talks to me about her my heart aches inside but I have to help him cause he’s my best friend. I can see them getting back together and I don’t know how gonna cope.

I need some help and advice to get over him.