My opinion may not sit well with many, but if you are not a temporary person, and are truly in it for the long haul, then marry this girl now and move in with her to become a family. If you want to be the father figure in this girl's life, then you lead by example and settle down with your girlfriend. You go ahead and take on the title as the head of the household (which is something you already believe in), and you tell your wife that you don't want the exes other than her baby's father hanging around to see the girl. If your girlfriend refuses to listen and will let whatever guy around her, well that's her choice, but that is a probably a bad sign, and you should consider finding another partner. You need to be straight forward and talk to her about that now, because if she's not invested on giving the child just one stable father figure, then you should back out before the girl gets even more attached to you. In my opinion, if you are not right to settle down *right now*, then it's probably too soon to be thinking about these things, and it would be wise to get yourself squared away beforehand.