I think it is possible to be friends with someone you don't agree with on political issues if one wants to be. It doesn't work, in my opinion, if people try to insist on talking about it with each other, or try to insist that the other agree and admit the error of their way of seeing the world. I have friends who are deeply religious and I am an atheist - we know the others stance - they think I will burn in hell and I think all religion is myth and theirs in general is misogynistic and hateful. But we just don't talk about it - we have fun playing bridge or biking or whatever and just don't insist on fighting about it.