One does not simply... walk away from the endings. Unfortunately, no one can be told, how bad they are. You have to see it for yourself.
Also, the fact that people still post here does not necessarily mean that they pretend to have quit the game.
I've seen all the endings. The first time I finished the game I was pretty much ecstatic. (picked Synthesis btw) I'm not lying when I say I loved the Catalyst, it's not a troll move to engage people like.. eh, you. The Reapers finally, for the first time in the game, made sense. They finally had a beginning... and an end if you so wished. I can't fathom that people would rather have had the Reapers just be the Reapers, with no reason as to why they exist and where they came from. Or prefered the Dark Energy plot, which was just awful.
For me, the ending ruined the game for me. It broke my heart to know, what we did was for nothing other than getting the characters I loved killed. Garrus my Shepard love interest died a slow painful death on a non dextro world without Shepard being their with him in his finale hours. That's not bitter sweet that's just horrible writing and gives you a hollowed feeling of guilt afterwards. A bitter sweet ending would be having Shepard die in his arms or placing flowers for her at her grave on Pavaln or earth if Kaiden was your LI. A true bitter sweet ending wouldn't leave you with that hollowed feeling of guilt for what you've done.
Aren't you still playing the game? 
And you felt guilt for saving the galaxy? What?