@pollyputthekettleon32
Woah, that is AWFUL. Some friend! Even if her dad DID say that (and I am wondering if he actually did!) why did she need to tell you? 
Like everyone on here I would NEVER have charged my friend for taking her to the pub or restaurant for our lunch, even if SHE had asked ME.
This is the type of person (and her dad if he DID say this,) who will want to split stuff exactly 50% down the middle. Like if you went for a meal, and your meal was £10.50, and theirs was £9.50, they would never just chuck a tenner in, they would INSIST they got their 50p change. Tight arsed fuckers!
Urgh, I fucking HATE people like this. 
Did you offer the fiver for petrol, or did she ask?
@amazingpostvoices
I find this entire OP confusing!
I would never in a million years think to offer petrol money to someone who drove me for 15 minutes. Let alone to a lunch they arranged.
Why on earth would 30 she be discussing her petrol consumption down to the level of individual journeys with her Dad?
Finally I can think of no sensible reason for her to have passed the comment on to you. Personally OP I’d let that friendship drift.
All of this. As I said, why did your 'friend' have to pass on her dad's spiteful remark?
It reminds me of one time, (around 10 years ago,) when a 'friend' of mine felt the need to tell me that her sister said I have put on weight since she last saw me. Why tell me? It's obviously going to upset me.
This 'friend' is no longer a 'friend' by the way!!! 
As has been said, I would start giving your so-called friend a very wide berth.