Ask Amy: Son wants to kick freeloading dad off couch

Dear Amy: My parents divorced when I was very young.
My brother and I were raised by our hardworking mom without any financial support from our dad.
We are now in our 20s, have gone to college and are working at successful careers. I am married.
Dad has always been a freeloader. He’s never had a steady job and relies on women to house and support him. His lifestyle includes drinking and drug addiction.
As adults we have tried to help him through the years, but without any success. Because