Is it worth continuing in this relationship?

I have been dating this woman for nearly 2 years. She has two girls from a previous marriage (we have both been married and divorced twice). She says she loves me and I know that I am very much in love with her, have been since I first saw her.

The problem has several aspects: 1- While her ex (the father of both girls) had partial custody he abused them. Both girls show all the classical signs but only the youngest, 6 years old, admits that he did. The courts do not believe the girls and so custody battles continue. 2- because of the abuse the youngest girl is very stand offish with me, even though I spoil all of them and try everything I can to win her over. The oldest daughter 9, loves me. 3- She and the girls live with her parents and have ever since she left him 3 years ago. 4- There is never a lot of time for me because she works long hours and feels guilty about not spending time with the girls so she devotes most of her time to them. 5- Because both ex's turned out to be real ******* she has put me in that category if we were to get married so she says she will never get married again to anyone. HELP! Do I stay and keep trying or do I move on? I really do love her and want to spend my life with her and I do believe that she loves me. I see it and I feel it when we do have some time together.