A good way (tho not the only way) to respond to PA comments is to call their bluff. If they’re hinting that you’ve left something undone, ask them straight; “Is there something you wanted me to do?”. If they’re hinting that they’ve been left out, clarify; “You don’t feel left out do you?”. If they insinuating that you’re being a meanie to them, ask them; “Are you ok with this? Is there a problem?”.
That leaves only two paths forward. Either they’ll tell you straight, or they wont.
Unless they’re prepared to tell you straight, you can’t make it your problem. It’s their problem. All you can do is to keep trying to help them share their problem properly, not passively.