In English there is a very specific usage of the phrase “What can I do?” that has nothing to do with the literal usage of that question. It’s when that phrase is used as a rhetorical question where the speaker is indicating that there is nothing they actually can do about a particular situation.
Jane: Your husband never takes you anywhere. He is always having affairs, and he yells at you night and day. Why don’t you leave him?
Jill: What can I do? I’m madly in love with him.
Less related to relationships, and in this case having the added nuance of expressing helplessness on the part of the speaker, because they are trapped by circumstances:
John: You have to fire the new chef. The employees hate him. Everything he cooks gets us a one star review from the critics, and some say he’s stealing from the register.
Joe: I’ve heard, but he’s the son of our main financial backer, without whom we wouldn’t last a week. Keeping his son as the main chef is written into the contract. What can I do?
Is there a phrase in German that is equivalent and is used across different topical context like the way “What can I do?” is used here? Any German idioms that fit this application?