Signs a relationship is in trouble

https://www.youtube.com/watch?v=qadSvKa2eHY

February the 15th is the most common date partners break up. Gee, that's today.

Please remember to bring $1 for room rental, and please patronize our hosts.

What are the signs and symptoms that, based on your experience, indicate there is trouble in paradise?

In what ways were you incompatible with your partner? What was discussed, or found out too late?

To what extent is your discomfort due to your personal issues, and just happen to be reflected in the relationship?

'What's the difference between avoiding problems, and "faking it until you make it" ?