DEAR ABBY: My 18-year-old son and his fiancee have been kicked out of a few apartments and have asked to live with me. Wanting to help him, I agreed.

When they moved in, I gave them four rules to follow: No drugs in the house, no sex, no coming upstairs after 10 p.m. and the dishes must be done every night or they will pay $400 a month rent.

Well, a week ago I caught them doing drugs, so I called the cops. They were arrested that night. They are now asking to come back. I refuse to allow it because I have an 11-year-old at home with me and another 18-year-old who I want to keep away from this kind of influence.

My son keeps texting me and trying to guilt me into changing my mind because he got his fiancee pregnant. Where I live it gets very cold, but I need to show my other children it's not OK to do drugs.

Am I doing the right thing by not letting them come back, or am I a heartless mother like he says?

- Mom of Tough Love

DEAR MOM: Regardless of what your son says, you are not heartless. You took him in with certain conditions. He and his fiancee abused your trust, and you handled the situation wisely.

If the girl is really pregnant, she should not be using drugs. If she's hooked on something, she needs to get into a rehabilitation program ASAP. If she has parents, perhaps they will take her in. But you have done your part, and if you allow your son and his girlfriend to stay with you, they will continue to break your rules and you'll wind up responsible for them and the baby - or two or three. I advise against it.

TO MY JEWISH READERS: Sundown marks the first night of Passover. Happy Passover, everyone!

Dear Abby is written by Abigail Van Buren, also known as Jeanne Phillips, and was founded by her mother, Pauline Phillips. Contact Dear Abby at www.DearAbby.com or P.O. Box 69440, Los Angeles, CA 90069.