You know it just now occurred to me that those options aren't mutually exclusive. It could start off as #1 but then "X" happens and acts two & three are #2.
If handled poorly, yeah, that would be less than ideal.
As I said though, I would suggest that it not be about loosing her boyfriend so much as it being the latest in a long line of traumas and that the conversation be more about the stigma of mental illness than what happened to Vision.
Literally the first time we see her it looks like she's not quite all there. Now that could be just a side-effect of whatever Hydra did with the sceptre to give them powers, but still it's not hard to sell the idea that she has a pre-existing condition or at least a history of some kind of mental illness.
She's certainly been through enough with what happened with her parents to be left with some degree of PTSD or something similar.