Yes. I know if it happened to me, I would be frustrated and beyond furious. My pal, shortly after the onset of his aphasia, became completely and indomitably positive in his attitude. Which was I suppose great for him, but more frustrating for me, because I knew none of his/our clients could conduct business with him/us without wondering whom in hell they were talking to, whether he was on heavy drugs and whether “next week” meant “later this afternoon” or “next month” or “sometime in the future, time unknown”. He was perfectly aware that he had the affliction yet blissfully unaware that he could not transmit coherent meaning and likewise unaware that it was patently obvious. It turned pathetic and pitiful and I was not happy with how I dealt with it.
I don’t think there’s any good way of dealing with it, and you did the best you could. God knows that you meant well, and now so does your pal. So all is well.
My Mom has “Post stroke aphasia”. Getting better but comes and goes. Sometimes aware of it, sometimes not. It’s better when she’s not aware, for me anyway, cause when she is she gets frustrated as hell. I’ve learned to cope, it’s a pita, but damn!