We can argue this until the crows roost but it's not going to change anyones opinion. I think he's just as bad as she is and nothing is budging that.
Thing is, I don't think you're actually engaging with what those who
don't think he's as bad as she is are arguing.
All i'll say from a girls perspective in this scenario is the second he told her he didn't know when he'd be back after saying he'd only be gone for 2 weeks with how important things were for them both is the second some of us would have dumped him.
There are girls that would have been that pissed off they didn't want to have anything to do with him so ghosted him.
I appreciate you guys only seeing one perspective but he left her behind when things were most important for their future both together and in their careers. It's a very important part of their lives which she couldn't put on hold while he has no idea what he's doing. . . .
Expecting her to wait for him when he doesn't know what he's doing is just as selfish as her not giving him closure.
There are a number of us, at least, who are in complete agreement with you here. It's not a matter of "only seeing one perspective." The MC doesn't honor his commitments to his girlfriend, and he makes it worse by making a promise to her and then breaking it. I was raised to believe that a major difference between boys and men is men keep their word, and he doesn't. He deserves to get dumped for that, and I'm not sure anyone really disagrees.
However. There is a meaningful difference in their motivations here which has to be given due weight. For all that the MC screws up, he's motivated by compassion. He's trying to love his uncle well because he's family; in the process he fails to love his girlfriend well, but however badly he botches it, he's still making some effort. Yeah, he's clueless, and he has some growing up to do--and which of us doesn't at ~22?--but there's some good there, too.
Fiona, through all we've seen so far, isn't clueless, she's selfish. We don't have any indication that she sees the MC as an equal who must be respected and treated seriously--those who're convinced he's the beta to end all betas (bettas?) do have some evidence here; what we see is not her planning their life
with him but her planning their life
for him. The shock and betrayal with which she responds to his intent to leave East Lansing seem to me to be more "You're not allowed to do this!" than "I'm going to miss you!"
(And by the way, one caveat: far too much is being made of the effect of this on his academic future. A large swath of my family are Spartans, including a couple who went on to earn Ph.D.s; MSU is a solid school, but we're not talking Harvard here. He'll be able to carry on with his program and graduate--he'll take a hit, but it's not like he'll be banned even in the near term, let alone forever. The biggest penalty for him is likely to be financial, depending on whatever scholarships he had, because he's probably lost that assistance for good.)
I said this before, but it needs to be acknowledged: the MC shows concern for those for whom he should show concern, but Fiona doesn't. We don't see her showing any concern for anyone but herself. It's not like we can generalize from that (that would be to call her a sociopath and/or a narcissist, and we have nowhere near enough evidence for that sort of accusation), but we can say that at a fairly intense moment, she operates completely without empathy even for the MC, let alone his family. I think if her reactions had been anything other than "Me, me, me" that folks would be far more supportive of her and far less of the MC.