Reminds me of a similar thread I started awhile back.
http://www.christianforums.com/t100047
I don't think that by putting yourself in a situation where you maintain contact with this guy, you're turning the other cheek. If you're putting yourself in a situation where you know that on a regular basis, he is going to do something that makes you angry, and that basically you have a feeling of dislike towards him because of this, how is that turning the other cheek any more than having a talk with him and saying something like: "Look, I don't want us to hold any grudges with one another, and in order for me to do that, I need for us to have distance between us and not talk very often."
I can tell you that with my ex, I would forgive him, and then he would constantly come up with something for the express purpose of riling me. That wasn't a healthy situation and I was just feeding him any time I would respond to him. I was also very angry with him. Now that he has finally gotten the picture and stopped contacting me like that and we don't talk unless there's a reason to, I don't have that anger in my heart towards him and I feel like I can love him as a fellow Christian (from a distance!).
Turning the other cheek is about finding a peaceful solution to the problem instead of repaying them for the bad things they've done. In some cases, the most peaceful solution is to put distance between ourselves.