You are right about you can not control her new relationship or can you control what happens to her emotionally. Now for the friends you can be friends but that will depend on her willingness and how much it will hurt you emotionally. If you are not emotionally detached from her then I would not do it until that happens.
Now is it over between you two? Who knows. No one can predict the future. My parent know a couple that were divorced for five years and they got remarried. But one thing is for sure is that you should not put your life on hold for her. If you do not want to date that is up to you but differently GAL.
Love is a decision. Genuine love is honor put into action, regardless of the cost.
Me:43 W:41 M:21 SS:25 S:19 D:18 BD1:3/16 BD2:10/16 W moves out 10/2/16