[IThrowAway]

2 months ago I went through something similar. Interviewed at this company: 2 phone interviews, one skype call, and about 6 hours of onsite (flew out to a different city).

I got another offer so I contacted the manager from the first company and the recruiter. Manager calls me up and we discuss the offer, things seem to be going well, I was happy with the offer and we agree to move ahead. Recruiter contacts me the next day saying I should be getting an offer letter by the end of the day. Next day I get a call from the recruiter saying the HR department wants to see my current pay stubs and tax documents from the last year because they want to ensure my "integrity". Things went south after that as I didn't want to give my personal information. I really liked the team and the job (what was described to me by the team / manager).

I was in the same state as you are right now, didn't really sleep properly for 3 weeks. I would suggest taking your mind off the job hunt for next week or so - - start a new project - learn a new technology that you have never touched before - hike / take long walks (helped me a lot as it opened me up to a new perspective) - volunteer (tech talks / meet ups)

Honestly, a job or a company doesn't define who you are and what skills you have, it is YOU who makes the difference.