How do you recover mentally after a failed startup?

Hi,

I started a company in 2019 after graduating from from undergrad.

This is a bootstrapped business and I built it as a solo founder.

Although it managed to get some traction (tens of thousands of users), I've basically at my wits-end on monetization.

The business is only generating ~50-60k per year in profits, and I've lost hope on seeing a path to scale it further.

When I graduated from college, I decided not to pursue significantly more lucrative option to work at a FAANG company and instead spent the last 4 years working extremely long hours on this business.

Over the last 4 years, I've basically done nothing but work 7 days a week and despite doing this, I have nothing to show for it.

Meanwhile, my friends from college all took 6 figure jobs, have traveled, made new friends, found gf/bfs, learned a ton, got promoted in their careers, etc.

Obviously this is entirely my fault and I take 100% responsibility for my decision. To fix my fuck up, I've started prepping LeetCode and plan to start interviewing for a job in 1-2 months (ya I picked a great time... I know)

Has anyone else been in a similar situation?

How do you recover mentally?

I feel like my self-confidence/feeling of self-worth has taken a massive hit. I've basically wasted the last 4 years of my life and I feel a deep sense of regret. I can't help but feel like these are valuable years where people build up their friend circles, finances, find a partner, etc.

I've done none of that and I feel like I'm extremely behind everyone else now.

Would love any advice. Thank you.