I think everyone probably thinks this to a degree. When you play more, you learn to not let this bother you as much. Just yesterday, I was playing a hand where I folded K,2 off suit (I think clubs and spades respectively but I don't remember). Anyway, I folded preflop and I think 3 players made it to the flop. The flop then comes Kd,2d,6c (assuming I remember the flop correctly). A part of me was sighing inside because I just folded a hand that was going to flop two pair and the King was the top pair as well). However, mathematically, you make the correct decision by folding worse hands - even if the result sometimes goes against the majority. Take the hypothetical 7,2 off suit hand. This is seen as one of the worst poker hole cards you can be dealt. If the flop would come 2,2,2 then does this mean that the fold was "wrong?" No! You aren't going to flop 4 of a kind too often and if you called junk hands like this, then you would play every hand and lose much more long term. A lot of poker is playing percentages and shrugging off the few cases where the result doesn't align with the action that will be best most of the time statistically.
Anyway, back to me flopping two pair: or would have flopped two pair. By the turn and river, another diamond hit the board and one of the players made a flush. Point being that even my two pair would have lost. Even if my folded hand could have potentially won though, we must play the math to some degree (regardless of short term results/variance) and shrug off the times where we MIGHT have won and statistically, we will lose more with losing plays.