My answer to all three forms of the trolley problem is roughly the same... I almost undoubtedly wouldn't flip the switch, push the person, or sacrifice myself, but I endorse doing all three.

In the latter case, I would feel guilty about it afterwards (assuming the idealized version of the scenario where it's clear that I could have saved them by killing myself). In the former two cases, I would feel conflicting emotions and I'm not sure how I would resolve them.

Similar issues come up all the time with respect to, e.g., donating all of my assets to some life-saving charity.

I also often defect in Prisoner's Dilemmas, as long as I'm confessing my sins here.