That's a fascinating piece of psychology there, as much as it is sad.
It really sucks when a game you normally enjoy becomes stressful enough to no longer be a positive experience. It's happened to me before with a few games: Frozen Synapse, correspondence chess, regular chess, competitive EU3 mp - mostly slower, competitive multiplayer games. I've also pretty much stopped playing DCSS because I'm in the middle of a long streak of wins and don't want to screw it up.
Regarding part loss in Cogmind: I feel it. When I was trying to get a combat win during the event, I felt like I was running against a brick wall over and over.
These two posts I made were probably the height of my frustration. I think the only reason I kept going was because Happylisk and Agroesch were getting so close to their own victories.
Losing items in DCSS back when item destruction was around really sucked, but it's so much worse in Cogmind. I agree that the game largely revolves around inventory management, which is actually something I really hate in other games, but I don't mind it too much in Cogmind. There are always better parts around the corner.
What about those stealth/speed wins you did? I imagine you didn't lose many parts with that approach. Watchers are an endless supply of good utilities for that sort of build, and the only other critical items are flight units.
I've never been a big wiki contributor in other games, but the Cogmind wiki does need some love. I'd add to the Lore page if I had half a clue what the lore was about! I am slightly ashamed to admit I haven't read any of the story-related text in Cogmind, nor have I pondered too deeply Cogmind's existence and how he came to be - in the scrapyard. All of my focus has been on the game's mechanics. I certainly plan on catching up on the lore however.