What would you do if your SO's siblings hate you?

Christian • Hi, I am Christa. I am 22 years of age, and am with a man that I adore. We are planning to move In together soon.
So back in high school I made the mistake of breaking it off with my military boyfriend. He would have been gone for a while and we were still pretty young. We were and have always been pretty mad about each other and when we got back together, it was as if nothing changed. It was like a good movie paused and then just started where it had stopped. We are now planning our future together, but his siblings do not care much for the girl who tore their baby brother's heart out. They don't realize I tore my own out, too. We were too young to get married, but he was going to be overseas for three or so years. I didn't know what to do. Well now I just feel like hell, but I love him too much for it to cause any issues. What do I do? What can I say to make it all okay again? Will they ever like me again?