Should I leave it alone?

Broadway
My boyfriend and I have been together 21/2 years. Lately, this have been getting very boring. We have very different interests, which is now starting to come between us. A guy I used to work with and I have starting hanging out a little bit. Him and I went to a concert and out for drinks a couple of times. I have had a "crush" on him for awhile now and am very interested in seeing where things might go. Here is the problem, we are both dating people (he has been with someone for 2 months). I don't know if he is interested in me, although we have a great time together and flirt back and forth. So, what should I do? Purse this guy and see what happens? Or just leave it alone??
Should I leave it alone?
7 Opinion