There are a couple reddit subs that compile ongoing (as in OG post + updates) relationship advice posts, such as in r/AmITheAsshole or r/Relationship_Advice, for convenient reading. The two I've found best for interesting windows into messy life a.k.a. ideas for scenarios are r/BestofRedditorUpdates and r/BORUpdates.
As a sample, here's one that I keep returning to reread: AITAH for "misleading" my cousin and "destroying his marriage"?