It does suck more phsychologically. This asymmetric treatment of gains and losses is engraved into human behaviour.
Think about these two scenarios:
1) you have an overnight position, it gaps against you at the open. You are 5% (of your capital) down, you immediately get out and see it drop like crazy 20% more in the next few minutes. Naturally, you feel very good about being such an astute trader and having escaped this deadly drop. But chances are, very soon you'll forget about it and move on to other things, as it's just one of those decisions you think was right and you can't really take full credit for it, so no big deal.
2) same situation, overnight position, opens 5% down you immediately put in a market order and close it... at what turns out to be the low of the day. Not only that, the price rebounds in the next few minutes and climbs back and now you see you WERE right in taking the initial position. I guarantee, the extent of unhappiness you will feel about situation 2 will far exceed how happy you will be in case 1. Not only that, you will feel the pain for much much longer than you'll feel glad you swallowed the loss in the first scenario...
I'm not saying you are wrong that people shoudn't act this way, I'm saying they they do b/c gains and losses aren't treated the same way in our heads.