Looking at the joke closer, the last line does imply that something should be done to fix the problem. While I agree that a lightbulb does need to be changed upon occasion, it's implying that the person attending Al-Anon can and should "cure" it.
In other words, I think this sort of humor can be funny to the right people who are far enough from the cause of the hurt (I can repeat some of XABF's favorite phrases to people sarcastically now, and not be hurt by them, but think they're funny - although they weren't at the time), but for people going through this situation, especially now that I'm sitting down to look at it - it does feel offensive to me.