DEAR AMY: I am 20 and my girlfriend of six months is 19. Ever since we started dating, she seems to go out of her way to tell me whenever a guy hits on her, compliments her, or flirts with her.

Dear Amy: I’ve been with my girlfriend for eight months. Most of the time, we’re really happy. I believe we are very well suited for each other. We have common interests and our values seem to ...