DEAR ABBY: I have a next-door neighbor who is retired and takes care of his wife, who has dementia. He’s a nice enough person, but he has no personal boundaries. He is intrusive and knocks on my door while I’m working two to three days per week. My work area is close to the door, and if I ignore the knock, he just knocks again. I am on the phone most of the day for my job, and his incessant knocking is disruptive.

I’m sure he’s lonely, but he does have other friends. In the beginning, there was a bit of a friendship between us, but he started asking me intrusive questions the more we got to know each other and began saying inappropriate things to me. When I told him it made me uncomfortable, he just laughed it off.

I began distancing myself from him and even blocked him on my phone because he would text me often about silly, random things. That seemed to work for a while, but now his intrusiveness is ramping up again. Each time he knocks on my door while I’m working, I tell him he is interrupting me and to please not bother me during work hours. He isn’t getting the message and continues to do it at least a couple of times per week.

He isn’t dangerous, but I do not want to be friends with this person. I want him to learn some boundaries and stop bothering me, especially while I’m working. Any advice you can give would be appreciated. — ANNOYED NEIGHBOR IN THE WEST

DEAR NEIGHBOR: Because you have tried to rebuff this person politely, it may be time to be less so. The next time this neighbor knocks on your door, tell him plainly that you do not like being intruded upon and want it stopped. Tell him you have already blocked his texts because they were so frequent and annoying, and if he doesn’t stop stalking you, you will make a police report. After that, consider moving your work area to someplace farther from the door and — regardless of how long he knocks — do not answer your door.

DEAR ABBY: I have two sons. My older son, “Dan,” is 25; my younger one, “Jon” is 24. Dan suffered from depression. I got him help right away, and he’s doing well. Jon can’t deal with the fact that his brother has depression.

Jon met a woman who is 51 through a friend of mine. I had a gut feeling something was going on with them, so I looked at his cellphone records and saw that they have been talking. I think there is more to it. Jon doesn’t come home sometimes. If I ask him about her, he freaks out.

I talked to my husband about it, and he said to mind my own business — that it’s only a sex thing. I find it disrespectful and not normal. What should I do? I don’t want to lose my son. — NERVOUS IN NEW YORK

DEAR NERVOUS: Although you may not approve of the situation, at 24, your younger son is an adult. The way he conducts his sex life has nothing to do with whether he respects his mother. Your husband gave you good advice, even if it was something you didn’t want to hear. For your own sake, follow it.

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.