Hola papi-
Oh my! You sound so upset...i'm terribly sorry for whatever is going wrong...I've already mentioned on these threads that I am not good at the love stuff...I can use this opportunity to add that I am not terribly good at the sort of maternal advice...but I will do my best...
All I can say is, it really can only get better...Just try to put things in perspective...Love's a heifer (you know what I wanted to say...I can't curse here) but if there is anything I have learned in my old age

it is that if it is not working out, there is probably a good reason...cut your losses and move on (obviously, I have extremely over-simplified the situation because I have no details, but that seems to be my rule of thumb...keep in mind, though, that personally, when it comes to a flight or fight response, I will flee 99% of the time...and how!)...
Your graduate grades can be fixed, but are reliant on your mental health...your mental health can be salvaged just by trying to keep as positive as possible...Get some bluegrass music...I can almost guarantee that all of your woes will pale by comparison to some of the sad, sad stories they tell
I don't mean to make a joke of your situation...that's just how I deal...but seriously, just stay positive...things have a way of working out for the better, even if you have to go through a lot of hardships.
I dunno...hope that helps...