Do I try again or just accept that I am losing one of my best friends?

Text him, call him, talk to him. If you know that you still have feelings for him, then you should take a chance. The worst thing that could happen is have him say that he doesn't see you that way anymore or he doesn't want to be friends... I mean, he's already ignoring you, right? So I guess the worst that could actually happen is nothing change.