Am I wrong?

Okay, I'm a caregiver for a friends nana. She has had 2 strokes. One in 99, one about a year and a half ago. One messed her right side up, the other messed her speech up. 
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Problem is, for the past 2 weeks, she has done nothing but bitch and complain about anything and everything. Her husband passed away 3 months ago. I'm sure it bothers her, but my point in saying that was that when he WAS alive, he babied her. He never let her whine or complain, always got her way, did whatever she wanted him to do, and whenever. I'm 29 weeks pregnant. So this may be why I'm feeling like I'm in a crappy mood. For the past 2 weeks,  she hasn't wanted anyone's help (not even family), she's been distant from everyone, she yells, screams, gets smart, throws tantrums. And I'm OVER it. I love my job, and I love her. She's a sweet heart sometimes and we joke around about the dogs in the house and other stuff. But she just has those days where she'll smack at you or shew you away for no reason. Mind you, the strokes have not made her as bad off as she's making herself out to be. She's doing it because other people think "oh she can't help it." Which isn't true, she's just a spoiled brat that isn't being spoiled anymore. 
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I'm sorry if this post makes any of you mad. I just know that FOR HER, there is a difference in the strokes she's had, and being mentally challenged. And that's exactly how she's treating it. I'm doing this for my baby. So I have money. Because a job is inevitable. But I refuse to walk on eggshells for someone just because they were once a spoiled brat, and now can't be. Any wrong move and she's crying hysterically, shewing you away, smacking, or just saying hateful things to get you to leave her alone when all you're trying to do is help. 
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I just needed to vent. So I'm putting this as anon. Am I wrong...?