if all your and significant other's ex's in the world start becoming your chummy neighbors what would you do?
I wouldn't really mind since I usually try to let bygones be bygones. I sincerely believe people are more or less mature in one way or another barring those who show themselves to be petty and immature at heart.
But yeah, if people show they are willing to be friends, why stand in the way of friendship?
What I cannot stand is those who use friendship merely as a means to accomplish less savory agendas.