What were the warning signs before your co-founder relationship hit problems?

I would really love to hear from the community :) I am working on some longer form content in this area and hoping to learn more about what happened with your co-founder or co-founders. My co-founder relationship hit some big problems in 2014, and I am putting together a site on how to keep your co-founder relationship strong so that people do not go through what I went through. If you have a few minutes please chime in below with what warning signs you see in hindsight. The site is: https://healthybusinesspartnerships.com/#/select-questions *Still working on content and fixing some bugs.