Aahh, you do have a real dilemma girl. I can imagine being in that position and I sure will have a hard time deciding. I love my family and they are the reason that I was willing to sacrifice for them. The same way that I love my man and the Idea of finding living with him for life is a bliss. Not all women are lucky enough to have found Mr. Right. So its like the situation is between a hard ground and a rock.
Loving is a season. We do have a season for everything. You have done some sacrifices and I guess they have prepared for a moment like one day, you will have a life of your own. I guess they have already prepared economically so that when you stop working for them, they'l have the source of livelihood. Or if you think they have not, then perhaps its not yet too late to start saving and start figuring out how to quick start them.
Living for your own happiness is never selfish. As I've said, loving and living has its own phase and season. Your family came as your top priority when you were single.Then you wanted a family of your own, that's another season to consider.