I am obsessed with Max and Marcus on Ginny and Georgia. You can tell that they were not really going to be the focus of the show initially. They had very few scenes together, most of them were played for laughs, even their fight in the s1 finale was on the funnier side of things. The actors didn't read for chemistry with each other, I'm assuming that their chemistry with Ginny played the biggest role in the casting.
Something must have clicked for these guys in s1, because in s2 we get the Marcus episode, and we see just how big of a role Max plays in his life, outside of what Ginny knows about them. Also, being there for her brother and noticing his depression is the only good press Maxine got that season.
Then we get to season 3, where Marcus' storyline is a big part of the show, and we subsequently get more Max. It is easily my favourite part of the show (shush tumblr stop underlining my spelling of favourite, non-americans exist in this word).
Marcus values his relationship with Max, and her role as his confidant. In this season, he does not confide in anyone as much as he does Max, and we can hypothesize that the things he told Ginny in earlier seasons are stuff that she already knows (his dead best friend, his depression, etc.) In episode 4, when his father is lecturing him about responsibility, and he glances at Max for solidarity, and he looks so upset and betrayed when she avoids his eyes. He then proceeds to go crash out in her room at the mere thought that Max might not be on his side. Its why her telling their parents about his alcoholism triggers such a negative reaction.
In the previous seasons, we see moments where Marcus comforts Max. We see that in this season as well. She needs him as much as he needs her. But, through the flashbacks, its clear that the burden of caregiving is placed on Max, sometimes by her mother and sometimes by herself.
I am so looking forward to how their relationship is going to progress. I really do not know how angry he is going to be after rehab, and how his absence and lack of support from her friends is going to affect Max's personality. I think the former is going to be a larger storyline for her, since we close out on her sitting in the garage and missing Marcus.