Vindicating Marissa from the Oliver thing
I genuinely think Marissa gets way too much hate for the Oliver situation.
Was she wrong to dismiss Ryan's concerns? Absolutely. But I think people forget that the audience had access to information Marissa didn't. We saw Oliver's manipulation, while Marissa saw a troubled, vulnerable guy in therapy who was kind to her and made her feel understood.
Oliver was literally so good at manipulating people that even Seth, Summer, Sandy and Kirsten struggled to see what Ryan was talking about. He deliberately made Ryan look possessive and unstable, and given Ryan's past, it's understandable why people were having doubts.
Ryan was right, but that doesn't mean the truth was visible to everyone. Even he had to dig deep to expose Oliver.
Marissa should've taken Ryan more seriously, but there's a difference between criticising her judgement and blaming her for being manipulated. Oliver deliberately played her trust, and I don't think she should be vilified for failing to see through the lies.