It was really easy, I took a look at what was bringing entertainment and a satisfying challenge between myself and others and what wasn't.
And then I put all my 40k into storage because I realised it's a very poor system. So now I'm focusing on my main game, which oddly has become a quite obscure one, mierce miniatures Darklands.
With some of Mantic's walking dead and Necromunda on the side, since neither of those need masses of models and both have their charm. In the past I used to play WHFB exclusively and resisted other GW options except for skirmish level and that worked really well for me. A sort of return to this has turned out to be a good idea.
And I hold no grudge or judgment if others enjoy 40k, that's fair enough, it's just become apparent that it's an expensive investment for me just to get no enjoyment from.
I think part of it is being careful not to be swept up in group enthusiasm for something and that can be hard to resist if you play with a consistent and likeable group of people. But sometimes you have to disappoint others, particularly if you suspect a new game is just a fad.