Sorry for your loss, and dealing with things like that is rough. That said, also not uncommon around middle age and starting to experience those things. As well as more responsibility, less time for fun, etc. There's no magic answer, but over time you will find your way to enjoy the little things again. It's what your friend would want, as well as family.
Regarding thinning the herd, don't get rid of it unless you plan to truly never use it again.
I hadn't played fantasy since like 2007, and didn't intend to play again thus made sense.
Blood bowl is an example where i leave it, then come back to it often enough.
I play my Necrons all the time, thus will keep them
I have an entire army of Orks acquired in trade, sometimes fun to just have silly games (Kill team or 40k)
I got rid of space Smurfs, because they don't make me happy at all.
If you have no storage problems, keeping it is fine. Don't thin the herd and regret it is what I'm hinting at.