A situation came up with my girlfriend where I drove her to an event that she needed to go to that was a two hour drive away (so a four hour round trip). After we got back, I charged her for half of the gas that it took to make the trip and she immediately challenged my request. She reasoned that we both made the trip together so it wasn't entirely for her and that none of her previous boyfriends had ever charged her for things like gas money. After a bit of arguing she ended the talk by telling me that I need to be better at "conflict resolution". We have only been dating for a few months now and I don't want to cause an unnecessary fight, but I feel strongly that it is fair that I ask her for gas money. I recognize that I will most likely be the one driving us on all of our future trips so I would like to clear this up before the next event takes place.
My goal is to avoid conflict, but I also would like for her to understand and realize what it means to be fair in a healthy relationship. How can I talk to my girlfriend about paying for future trips when she was upset after I asked the first time?
Additional information from comments
We do not have a joint account and probably will not open one for the foreseeable future. It is a bit too early for that.
I am asking how I should go about still trying to get gas money from this latest trip and set the tone for future trips as well since I believe splitting costs like gas money is fair in an equal relationship.
I would totally be okay with suggesting that she drive next time. The only concern that I have in that case is how quick she was to challenge me when I asked her to split gas money as well as how she brought up the fact that none of her ex's ever asked for gas money. I haven't had an exclusive conversation with her about what traits an 'equal relationship' have.
The event was almost entirely for her purposes, I am just tagging along to spend time with her and give her a ride. She just prefers that I drive since it is less stressful and usually works out better logistically. Neither of us are broke but I think it is reasonable that we share the dating expenses in the case that it isn't one of us doing something special for the other (e.g. birthday dinner, gift, etc...)