Garry's Mod crashing in single player.

So I have a ton of addons, but, the issue is, I load up single player, if I click onto my other monitor to do things, the game will most likely crash, if I don’t it will have a higher chance of getting me in, further more what’s the best way to get rid of addons, I have pages of them and I don’t want to click the unsubscribe button that many times.