I see what some of you are saying, but I'm not really sure I agree with your viewpoint. I could just be reading into some things wrong though.
Here is how I see it:
If I'm in a solid friendship/relationship with someone, I believe I have control over who I let interfere with it or not..at least on my side of things. If the other person lets someone interfere, and that person decides they can't continue with the friendship/relationship, that's out of my hands. It's their choice. In which case, I'd realize the friendship probably wasn't THAT solid to begin with.
If I'm truly committed to someone, noone is getting in my way. The person trying to interfere would be the one I wouldn't want in my life.
If both are truly serious about the relationship, and feel at peace with God about it, it's your own fault if you let anyone else get in the way of it. Why give that control to someone else?
*Disclaimer for the above. Pay attention to the "and feel at peace with God about it". I know there are cases when God can speak to us, or people around us and tell us that we shouldn't be with someone as a friend or more. We might not want to hear that or accept it. To me, that's not interference. That's wise counsel..assuming it is Godly..