Not even close. Don't get me wrong, I absolutely hated the ending with a passion, I thought it was absolutely horrible, but honestly, with the Extended Cut out now, it's not too bad, hell, I actually think the Synthesis ending was pretty good, while Control was pretty good, and Destroy was decent. Refusal kinda irked me, though it made sense I suppose, but anyways, I went off into a rant. No, it didn't ruin the series for me, I'm going to be more wary from now on since I believe EA is the main reason for the shit ending, and now that I've seen what they can and will do, I'll be paying a bit more attention to the changes coming and how they look, but overall, I still think ME3 was pretty damn good, I refuse to let a simple ten minute fuckup ruin one of my favorite series' for me.