MIL tells me DHs “secret” what should I do?

[somewhatavoidant]

My DH has bipolar and has been in an elevated state since early March. It has been a difficult time although he has seemed calmer in the last week and I’ve started to relax thinking the hypomanic episode was over. We are visiting MIL with our 8yr old DS. Yesterday she said that DH had told her he stopped taking his medication 2 months ago. This would explain the recent episode. She has begged me not to tell him she told me. I’m trying to think of a way around it as I don’t want to cause trouble between them. However, deciding to stop taking his meds (and obviously he is free to make that decision) is a huge thing that should have been discussed between us as his MH issues affect our family deeply. AIBU to betray MiLs trust?

It can also be that getting it sorted might leaving I should say @bisset**

I can’t work out what that means...?

His decision to stop taking important medication and not telling you about it is very upsetting. He's lied to you. While you're doing your best to support him and keep your family together. I have to say, for me this would be an issue big enough for me to consider leaving permanently.
It's hard living with someone with mental illness. Lying about medication may be too much for me, especially with DC to consider.
Sounds like you need a full & frank conversation. How you found out isn't the issue.

I agree with a lot of he previous posters, but I think if you want a way of handling this, perhaps you could say that you are glad he seems to have settled down but reflecting on the last couple of months, things have been difficult and maybe it would be useful for him to review his medication with the GP (or whoever he sees to do this?) if he doesn't want to tell you he hasn't been taking it, he still has a way of re starting, and you don't have to end up in a black vs white argument?

Thank you so much for your insights and wise advice. I’m going to talk to him shortly & do my very best not to drop MIL in it. It seems he has stopped taking all of his medication, not just his MH ones. I need to get him to GP & psychiatrist ASAP. Thanks again.