not going to help anyway. midlife crisis and other related mental problems can never be resolved by outward solutions. you can distract yourself for a while with exciting new hobbies (like getting a motorbike) but it will come back and even harder at that because then you will feel like it's even more hopeless as even this exciting change didn't really solve the underlying issue. but some people also just get used to being unhappy and that's about it for them.
The midlife crisis is a need for novelty, specifically the brain is not stupid, it sees that everything around is either collapsing or freezing in place and it wants to fight that, reverting to the days of college when everything was about building up and dynamism.
If and only if you get back to the same levels of building up and dynamism of the college days , and you are still sad/depressed, you could claim that the thing is not outward related.
not going to help anyway. midlife crisis and other related mental problems can never be resolved by outward solutions. you can distract yourself for a while with exciting new hobbies (like getting a motorbike) but it will come back and even harder at that because then you will feel like it's even more hopeless as even this exciting change didn't really solve the underlying issue. but some people also just get used to being unhappy and that's about it for them.