Does the Misty sneak off to pee when your boyfriend's watching her? If so, I'd say yes, she's absolutely afraid to potty in front of him because of the yelling. You pretty much never want to yell at a puppy for potty accidents - they're essentially toddlers, without full control of their bladder/bowels and with an underdeveloped ability to recognize when they need to potty unless it's extremely urgent. Therefore their control over having accidents is really minimal, and trying to punish them for something they can't control just makes them confused and scared to potty in front of the person doing the punishing.
Interrupting a puppy having an accident with a neutral sound (I like to use 'whoops' or 'uh-oh', because it's hard to sound angry when saying them) and rushing them outside to finish is fine, and of course rewarding enthusiastically when they do finish outside. If you find an accident after it's happened, it's far too late to teach the dog anything, so the best course of action is to clean it up with minimal fuss. The old 'rub their nose in it' method just teaches a dog, again, that the person doing the punishing is scary and unpredictable around pee/poo indoors, not that their past action of pottying indoors caused the punishment. It's not really worth risking damaging the trust your pup has in you to punish at all with potty training.