I'm in that situation rn. Currently in the process of ending a 3 year relationship with a girl I was previously friends with. Thing is, we won't be able to cut eachother out, because the people she calls friends are mine also. So, if we were to go that route, she'd stand there without any good friends on her side, and I would feel terrible for her. That's why it's totally fine for me if we were to stay friends, because for me it's pretty easy to just keep my distance and respect her.

But it would depend on how the relationship comes to an end. I talked with people who said after half a year of not conversing or meeting with them at all, they could normally talk with them again without any bad emotions.