Is it fair that I'm the only one putting gas in my boyfriend's car

I've been starting to feel some type of way about being the only one putting gas in my boyfriend's car, but on the other hand I don't think I have a right to complain. I'll explain.

My boyfriend and I are 20 and 21. He's had his license since he was 16, but when he was 17, he was driving him and his best friend and best friends brother from soccer practice and a truck that was really large but not like a semi ran a red light and hit the car hard killing both his best friend and best friends brother. My boyfriend wasn't at fault at all. He went on the green arrow but he wished he waited a few seconds before turning on that arrow. He got a new car through the insurance claim but he doesn't drive it. He hasn't driven since. So he would Usually Uber. We date and I drive him around when he needs me to. He works from home doing billing for a dentist office so I mainly drive him to therapy or to pick things up etc. I am always the one putting gas in his car, however he lets me use it whenever I want. My car got repossessed and haven't had money to get another car yet so I started depending on his to get to work and stuff. Part of me thinks since I drive him around at times he should put gas in the car too. But another part of me thinks since I use the car way more than he does than I shouldn't complain. What's your opinions?