I suffer from OCD and it has recently been pointed out to me it affects my game play a lot. For example: my ammunition count must be a multiple of 5 or I start waste/throw ammo, I must have an equal number of potions before each quest, if teams split off into different areas and the teams aren't evenly distributed I leave the game.

This is sometimes a problem, like I can spend a skill point on something useless, simply because I think the skill tree looks unbalanced. But it is also very advantageous as I find myself checking every corner of a map and finding extra loot or quest related items which were hidden to me normally. As I am a console gamer, it also means I complete every achievement and trophy available giving me a good score. It also helps me in online gaming for instance in FPS shooters it is now mandatory that before entering a room I check my line of sight into the room, throw in a flash bang/grenade, check the left then the right corner before taking 5-10 seconds to ensure nobody is following me or likely to check out who just made that noise. I take a similar procedure in real life (except without the weaponry of course) but it makes sense I do this in games too.

I just wanted to know, does anybody else experience anything like this? My friend made a joke that maybe a person with a multiple personality disorder might play a game in several different ways and at first I thought they were being too harsh but the more I think about it, the more I think it is possible.

Edit: I'd like to thank all of you for your answers so far. I understand talking about this isn't always easy and putting up with it is usually worse. If I could I'd give each and everyone of you gold because you've all been fantastic. Some of your stories remind me how hard life is for people with mental illness, not just in gaming but day to day activities. Keep strong everybody!

TL;DR My OCD affects the way I play in good and bad ways but I never realised. Does anybody have similar experiences?