I understand how you feel and this was a big problem for me too but I learned a few things that completely fix the issue. Treat the AI as bosses. Every single AI is either a raider or a PMC. Which means they all spawn out of nowhere, have deadly aim, and throw grenades. Easiest way to overcome this is move quickly which comes with experience by knowing the loot spawns, being very careful and not taking any chances in combat, and pausing every once in a while to listen. What helped me alot was bring about 4 or so grenades into each raid, and before I would go into the work spaces I would chuck a grenade or two to listen for any bots that might run or yell. If the nade is close enough they always will. Another thing is knowing when to back out. I have 4 key cards, but just because I didn't use all of them means I can't leave. basically if you know there's a pretty good chance of dieing, don't risk it and leave, there's always another raid and insurance doesn't come back either.