While it's correct, we probably wouldn't say it, mainly because we hardly ever actually use "whom" in our speech. It can easily be reworded to be "She lives with a person who is hard to live with", which sound better and removes the need for "whom".

Yes it makes sense. Gramatically I think 'She lives with a person, whom with, it is hard to live.' May be more correct.

your picture looks so funny, hahaha…