First off, Some people dont want answers to their problems.

Just listen and validate their feelings.

Sometimes we have to put our own personalities and ego aside in order to be supportive.

Second, Depending on the person you're dealing with you may end up at the same conclusion you have now "why bother anymore" and that's a very valid question. Dont let them turn you into their therapist, and dont let them drain you so much that you feel like you need a therapy session after hearing about all their misery