I’m stuck between mother and wife after buying car

My wife and I moved out three years ago as the relationship between them was not good, though their relationship hasn’t improved since.

Part of the money that we spent buying the house we are living in was borrowed from my mother. We paid it back to her a couple of months ago, and after that, I had some money left. I used it to buy a car, mainly for work but also for personal purposes. Things got complicated after that.

My mother asks me to take her to different places every weekend, from visiting her relatives to going to the market, or events she participates in. My wife gets annoyed every time, saying that I use the car to serve my mother while not aiding her and our children even once.

My wife suggested to me last month that I should drive her and our children to a nearby coastal city so that we can have an overnight family trip, but my mother asked me to drive her to visit her relatives at the same time.

When I said I was busy taking my wife and children on a trip, explaining that I had driven her many times before and that it was a chance for my children to relax after their academic year ended, my mother got upset. She said I only cared about my wife though she was the one that brought me up.

I kept getting stuck between my mother and my wife since then and had to decide every weekend whether to take my mother or my wife on trips. I thought about taking both of them on a trip together, but that seemed not to work out because of the longtime discord between them. I have become scared of weekends.

On a side note, the money I used to buy the car was wholly mine, and my wife didn’t contribute a cent, as she wasn’t in for the idea of buying it at first. If I don’t sell the car, I will keep being stuck like this. But if I sell it, it would be hard for me since my work requires a car.

What should I do?