Feeling a bit lost

Not sure how to begin so I guess some background. Turning 40 next month and starting to feel more and more like a failure in life. I mean, if you’re actively working on yourself and putting in the time and effort, shouldn’t life get somewhat better? I’ve been going to therapy, started exercising, making the effort to be more social because I do tend to isolate. I don’t know, I just feel so empty. Almost like I’m drowning in a pool full of 8 billion people. Now therapy has done wonders on how to handle situations when I’m feeling like this. I guess the question is, shouldn’t these feelings be decreasing as time goes on? Seems like the any sense of relief or satisfaction in life is getting further and further away. The crazy thing is I started putting in extra time exercising, added some extra sessions, and got a bit more consistent journaling. All that because I felt this coming on. And it wasn’t enough. It’s just disheartening. Anyone have any thoughts?