Confession: I've stopped caring about our 4 year campaign

I used to absolutely love this campaign. Now I'm honestly waiting for it to be done with. We've been playing this campaign for four years, from level 1 to 20. We're in the final stages. But the game is taking longer to end than anticipated and the quality has deteriorated.

We use a lot of homebrew mechanics and items, which was great for a very personalized game, but the GM was never good at game balance. Nowadays, she has a lot of personal stress, so she's stopped listening to feedback and the story has become incoherent.

I still have fun, especially with the role play, but the rest of the game has become too messy for me to care about. The GM's noticeably tired of running the game too, she keeps forgetting to prep and it feels a lot less creative than it used to.

I've brought up my concerns two times and they've fallen on deaf ears even with other players, so it might just be my impression. I still enjoy the game most of the time, but it's lost its magic. I love hanging out with the other people at the table so I'd never leave, and I don't begrudge it the GM, you can't help your personal stuff after all.

But to be honest, I'd rather end the campaign next session on a high note than stretch this slow death out for another year.