Reply To: Is this a chesed that should be passed up?

Yes, you should have offered to help her. There is no harm in offering; even if she says no, she will appreciate the gesture. Furthermore, there is nothing untoward about you helping her carry her groceries to the car. Everything is completely public and there is no risk of accidental physical contact. I have definitely been in situations like this one and wished that someone would help me but no one did. She may want/need help or she may not, but you lose nothing by asking.