This is a very difficult situation. On one hand, you may want your ex to be happy. On the other hand, you may know that them dating your best friend will lead to awkwardness and heartache for you.
I would say talk to your ex, and your best friend. Gauge just what's going on between them, and take it from there. It could easily be nothing, but it could also be a serious situation. The question is, are you willing to watch them have the happiness that you desired with your ex, or would you be happier just leaving them behind?
Rape them
not worry about it. its ur ex
You tell your best friend that your ex likes her and see what she says, explain to her how you would feel if they went out and if you were okay if they did. but also, do not ever get in the way of what they could share.
If he is moving it is best to just leave things.
If you still have feelings for him you can't do much but talk with your best friend. If she is a good friend then she will not began a relationship with him.
MAYBE YOU SHOULD IGNORE..
If you still have feelings for her you to should get back together.
It depends on if your ex still likes you and if her friend is willing to help. If she is, then ask her to talk you ex into giving you a second chance.
talk to her about it. it depends how much she still likes her ex too. but the best thing is to talk to her.
if your ex likes your friend then you shouldn't really care about who she dates after that.
You discuss it with your friend. it's never a good idea to date your besties ex but if you honestly like the guy and he likes you than your friend should understand that your happiness is key.
Do nothing. If it is meant to be he will realise it sooner or later.