Don Chase & Sarah: What Would You Do

My stepson recently broke up with his girlfriend and now, he and his father want me to end my friendship with her.

We got along great and often went shopping and out for wine. Their demand has created a rift within the family because I don't believe I should have to end my friendship just because my stepson ended his relationship. My husband is siding with his son. Should I have to end my friendship? Are my husband and stepson wrong? They think I'm choosing her over them.