One memorable time of this happening to me was in round 3 of an improvers rapid late. I have a blog with the game, it was against a higher rated player too.
Why does this always happen to me?
I lost a winning game due to a misclick. so annoyingggggg
Keep in mind that it was not for the last time
I don't play fast games because it is frustrating losing on time or due to a misclick
Play rapid instead. A lot fewer misclicks. More time to think. You will improve more too.
When you're ahead, it’s easy to relax — but that’s when we slip. Make it a habit to double-check every move when you’re clearly winning.
It happens to me often. One of the worst is meaning to castle and instead just moving your King one square.

I lost a winning game due to a misclick. so annoyingggggg