Have you ever snapped when irritated?

But just to make this even better, snapped at a family member with serious health issues?

I feel terrible..my sister has had seven years of awful debilitating pain and twitching in both legs. Most doctors do not believe it's diabetes related as neuropathy is typically burning, tingling etc. she's had a very brittle case of diabetes type 1 for 26 years 😟
And now on top of the awful undiagnosed pain in legs, she's developed horrible neuropathy in her feet. She can barely walk, and it's numb daily, it's just a hell for her. She vents and talks about it daily, and for two years I've not said much when it gets emotionally too much for me. We talk about it around the clock, daily. And I just snapped and yelled, "I know you have pain I know!!"

Yes it was a human reaction to occasionally be exhausted from talking about endless health issues, but she's the one DEALING with it. I just felt SO BAD that I said that. She's beyond strong, beyond human ..what she deals with is truly unbelievable. I buy her little care packages sometimes but I wish I didn't snap.
She's the most wonderful person I've ever known. Anyway I just had to vent for a few.
I'm praying she gets some real relief soon or help.