Do any of you NFP's still maintain friendships with some of your old flames even while being in a committed relationship?
Not usually, I fit the ENFP stereotype of sticking around far too long for my own good. By the time a relationship has ended, there's usually nothing that would really make me want to keep the connection alive.
How does your opinion change of the person whom you devoted so much of your love towards, and what's to say that continuing to be around them, will not potentially rekindle the flame?
There is one ex, that I wanted to remain friends with. She broke it off with me. I may have had a bit of my old feelings for her, but I didn't go looking for her, until about a year after our relationship had ended. When I found her, she was in a pretty serious relationship. I kept it extremely friendly, because I certainly had no desire to mess that up, but she started sending me racy texts, making it pretty obvious, that a friendship was, unfortunately, not possible. I just let her be, and silently disappeared.
What happens to the deep connections one may have with friends of the opposite sex, once they have established a long term commitment with someone, say in terms of marriage?
This is a bit of a different question, and something I struggle with a lot, because most of my friends are women. None of them are married, at the moment, but their lovers usually feel threatened by the emotional connection between us. I can't say anything, so do most of the women I date. There's usually some redefining of things between us, less flirting, less time spent together, things like that. It's a little hard to deal with, because I miss the closeness, but I make an effort to make it clear to their guys, that I'm the least threatening guy on the face of the planet. I don't believe in helping people cheat. I won't say that I haven't, but that was quite some time ago, and I quickly came to realize the error of my ways.