Honestly I know mordecai gets a lot of hate after rigbys graduation but i understand where he’s coming from people like to point out about what rigby did in the movie where he switched his acceptance letter and don’t point out why mordecai forgave him so using that as in excuse to justify mordecai actions is kind of irrelevant since it doesn’t really matter anymore. When I had rewatched the series multiple times and again when lost tapes was coming out I realised that there was an ongoing arc between both mordecai and rigby during season 5 which led to the events of rigbys graduation. Mordecai was questioning about what he wants to do with his life he has been wondering if what he wants to do after he leaves the park and also he realised he had a lot of growing up to do which was also part of his story arc his relationship with cj helped him realized that as well I always thought of his crash out in dumped in the altar was a big indicator that he needed to actually grow up and he wanted to move forward with his life because both his relationships were holding him back. Rigby was starting to mature during season 5 and his story arc was basically him not needing mordecai help with stuff and he was also starting to get his life together while also developing a healthy relationship with Eileen throughout the show rigby have always been a lazy slacker while Mordecai had to pick up his work but as the show go on and after Mordecai started dating cj rigby have been growing and maturing a lot since hes been left by himself with Eileen which caused them to form a relationship and after they got together rigby started to move on with his life he decided to get his highschool diploma so he could be a better person and better boyfriend to Eileen. Now in rigbys graduation mordecais jealousy towards rigby was actually built up especially in Eileen’s flat screen or skips in the saddle him seeing his lazy and incompetent friend actually moving on with his life have to been pretty much depressing for him since everyone in the park is also moving on with their lives as well mordecai have been very much used to being the combatant between the two I’m pretty sure he was expecting rigby to stay the same and I completely understand mordecai because not knowing what direction you want to head in life after everything he endured is very sad. Anyways that my opinion about the whole thing 

Unpopular opinion about mordecai