Tyler I'm really sorry to hear about your car
I know this sounds stupid, but it's just a thing & it doesn't define you, in a sense you think it does but it really doesn't.
Also, even if you'd had it insured with comprehensive coverage, you'd be on the phone right now with some moron that doesn't know the difference between a valve stem & a supercharger arguing about what the car was worth, and you'd lose, they have this damn formula that they go buy unless you pay for extra coverage & if they realize the performance mods you did they'd prob deny you insurance anyway.
I love cars & bikes, but after I totaled 3 of them and tried to tell the ins company that they were collector's items, or were in literally perfect condition, etc, I gave up & started buying & running stock stuff like the rest of the lemmings

(I never had anything I'd invested the kind of time & $ youd managed into your Mustang though, it was a nice ride).
As far as the break up, they royally suck, but the fact is, the more people you date/have relationships with (up to a certain point) give you a foundation for a better relationship in the future.