I don't take my personal safety or the safety of my family seriously on a part time basis. When I made the decision to carry a gun, I made the decision to carry it, not leave it at home or "forget" it in the safe. I also made the decision to be as proficient with that weapon as I possibly could, and I train as much as the ammo budget allows(and then some

), so that if some butthole trys to harm us/me, I will be ready.
I cannot fathom "forgetting" to holster up in the morning/evening before leaving the house, and can only advise that someone who "forgets" a firearm may need to take a second look at why they decided to carry one.
OP, you can scenario yourself to death with what ifs, but the truth of the matter is even if you run 10,000 "what would you do if" scenarios at home or in your training, the day you need that gun to possibly defend yourself will play out like nothing you've practiced before. I can promise you that, and I speak from experience.
Be armed, be trained, be ready, be willing, be able, and be alert.