It takes maturity to process and understand that your boyfriend loved and lost before you — but he’s with you. And he’s so much with you that he’s even taking you home to meet his parents. This is a big step in a relationship and a sign that he’s serious about you.
As for his one girlfriend he loved before you, I think it’s understandable that he didn’t want to be with her because she had two kids already. Whether or not you agree, it’s a clear and understandable position for someone to take. Some men don’t want to be stepfathers. Some women don’t want to be stepmothers. You and your boyfriend can have this difference between you and still have a successful relationship.
Likewise, it’s very understandable that when he did change his mind and told his ex he finally wanted to get back together with her and she said she didn’t want any more children, even with him, he felt that that was a deal breaker. Rather than judge someone on their preferences, accept them. Everybody has differences. The question is, are the differences too great. The reality is that your boyfriend had feelings for his ex, but they would never have been compatible. Their real life day to day differences were too great, and were deal breakers. That’s the way love sometimes goes.
It’s important to know what you want from a partner because while love is great, there are so many real life obstacles to long term relationships that if you can stack the deck in your favor with compatibilities, you stand a much better chance of a long and happy life together.
So tell your boyfriend that sometimes you feel hurt when he raves about his ex-girlfriend and how much his mother loved her, and that you understand that you both have pasts, but you”d really like to feel like number one with him, as much as possible. And when he does make you feel like number one, reward him generously with affection, sex and little gifts. “You make me feel so special,” is a great line to start with when he does right by you in this way. Men want to be successful with their women, and if he can make you feel great, he’s going to feel like he’s providing emotionally for you, and he’s going to feel good about himself when he’s with you. That dynamic is essential to a great long term relationship.
I have a feeling that with good communication between the two of you, things are going to straighten out very soon.