Not every kid gets the parents they deserve. I’m sorry you didn’t have a loving home to grow up in. But here’s the wonderful thing: It’s never too late to have the loving relationship and support of older, wiser people in your life. But first you have to give up on the idea that you own folks will ever do it for you. It may be that you aren’t allowing yourself to get close to older people you know because you are still holding on to the vague hope that your parents will be parents to you. They can’t. They won’t.
What you are calling jealousy is the very human longing to have caring mentors in your life. Since you don’t have that, you think it will make you feel better if your boyfriend doesn’t have it either. I want you to know that it’s human to be jealous. It’s human to want to keep your boyfriend to yourself if you feel like you are competing for his love and attention. But neither jealousy nor distancing him from his family is a solution to your need for parental love.
A more useful solution is to open yourself up to relationships with older people. Allow yourself to get close to a special teacher or an older person you meet through charitable work or activities you enjoy. Look around. There are plenty of people your parents’ age who are delighted by friendships with younger people. If your relationship with your boyfriend becomes even closer, you may even “adopt” his parents. That can be one of the great things about marriage — a second chance at an extended family.
I wish you well.