It may not be, but all we ever have to give advice on is what they say. We could guess ourselves into oblivion as to whether something else is going on. For now, we have his assertion that they are best/close friends, which would give him a good view into her life, and that she is dating aimlessly and pushing men into her kids' lives. 

Personally, I didn't get the impression he's a meddler, just that he cares about her and her kids and is concerned about the effect her actions are having.