Who is OP? I'm the one who posted. I'm COCap. My specific age is not important. Wonder where you see that info. Opponent player who made the comment, "Please don't hit balls so close to me" is almost 70 I think. She used to be 4.5 a couple of years ago. My partner who quit trying is 52. Trust me that my partner is almost 4.5 (rated 3.9998 on tennis record) and she hit the ball exactly where she needed to hit it with total control. It was a great shot!
Although this was social tennis and we were not playing at anyone's club, we did not expect to have to hold back on shots. It has never happened before and we have been playing lots of social 4.0 tennis lately since there are no league matches right now.
Kind of depends on how your partner interpreted the message..Maybe she thought your opponent was trying to intimidate with seniority or was acting entitled when in fact your opponent was just asking "please be gentle with us because we cannot move as quickly as we used to, and your shots are harder than what we are used to."
Either way, I think your partner could have handled it better. Probably the first step is to ask how your partner interpreted and felt about the comment. Whether she owes you an apology, well that's her decision in my opinion.. You can choose to invite her one more time, or not invite her at all.