Leo never treated JJ as a partner, rather some ornament. Evidence, when they broke up, Leo went to the bar to 'hook up with people' yet got upset at the supposed notion of JJ doing the the same.
During the warehouse scene, JJ thought Leo was going to ask to get back together, but noo Leo was like "wanna be f buddies bc I need my luck back thanks." Leo's intention while walking in the warehouse was not to mend their relationship, rather just get sum 'Fortuna'. But JJ was more than glad to get back to together bc he said "yeah sure—" before Leo finished his sentence.
And in the scene where JJ says he wants to go on a trip, but Leo says it's too 'tiring' but literally the next moment got up to go to a party. He's never actually done something JJ wanted. That was fine with JJ for a while, but eventually there was a breaking point. Instead of feeling loved or being an equal, JJ just felt used.
I'm not saying JJ hasn't done some fault here, but saying LEO isn't at at fault at all is INSANE.
Ppl who says Leo deserves bring treated like shit? Are you all okay? Leo only knows a rich lifestyle, if JJ doesn't fully communicate how was he supposed to act better? No one deserves to be treated like that with 0 explanation.