Sounds like you need to go spend a week in the backcountry of Death Valley before summer heat takes over. The wildflowers are blooming, you can still see snow capped 13K' peaks, you can sleep in a tent or under the stars or the bed of your truck/jeep or go to the hot springs with the other burnouts in Saline Valley (it's absolutely beautiful). Oh, and everything I've just described is free... you provide the transit, everything you need for a week alone, and your thoughts. Every time I felt this way that's where I would go, alone, on an enduro, and come back to the city and whatever I was describing my life as at the time, with the understanding that everything matters and nothing matters, but that complaining doesn't fix the underlying issues of being human.
Stop doing whatever is making you miserable. Get a break, otherwise this feeling you described only gets worse and the only place it leads to is a short life of existential pain and suicidal ideation.