There has to be a reason she doesn't approve. Either the girlfriend is not someone your ex feels the children should be around , or she is jealous. In which she will need to move on. As long as the children are in a safe environment, and do not feel threated by her... example: you spending too much time with her and not with your children. Your ex needs to show your kids that she can get along with her too. Who knows maybe she will be in the family some day? I feel that after a divorce.... the boyfriends and girlfriends need to stay out of the picture for awhile. You both still need to prove to your kids that the both of you are there for them. There's nothing wrong with going out once in awhile, just don't get hooked on that "one one one" thing.Go out with different people. Nowadays there is too much of the kids getting attached to the boyfriend or the girlfriend, and then there's a break up and the kids are left standing there again with someone leaving their lives.