I have found research support and a term for my idea:

"4. Paradoxical therapy

What if, instead of trying to suppress a worrying repetitive thought about, say, death, you head straight for it and concentrate on it?

It seems paradoxical that focusing in on a thought might help it go away, but some research suggests this can work. It's based on the long-established principle of 'exposure therapy': this is where, for example, arachnophobes are slowly but surely exposed to spiders, until the fear begins to fade.

This approach is not for the faint-hearted, but research suggests it can be useful when used by those tackling obsessive thoughts and compulsive behavior."

8 Ways to Defeat Persistent Unwanted Thoughts — PsyBlog

This link also discusses the obvious reality - thought suppression does not work. "Unfortunately, as many studies have shown, thought suppression doesn't work. Ironically, trying to push thoughts out of mind only makes them come back stronger. It's a very frustrating finding, but one that's been replicated experimentally again and again."

It is bizarre that you and he would go to so many counselors and nobody would tell you that, because it is entirely obvious from personal experience and replicated again and again in research. The question is, what did all of those counselors get paid for??

Since you are saying "we don't know how to make those thoughts go away" here, I assume that you verbalized that to the counselors as well... and nobody has suggested paradoxical therapy? In the world in which pretty much everybody with physical pain has been told at least once to try to focus on feeling the pain rather than trying to not feel the pain? And you guys were not counseled in that fashion, ever?