Keep the car and see how it goes. You can always sell it later if you do not like having it with you.
We liked our paid-for car when we bought our motorhome. That car would not be a very good toad and we did not have the towing apparatus or any towing experience. So we kept the car as a chase car. We have been fulltiming for 10 months, still with chase car. Like you we do not move all that often and try to keep our travel days fairly short, so having both of us drive is not a big deal for us. Maybe someday we will replace the car, invest in towing apparatus and begin towing, but for now chase car works fine.
Most of the time we would be able to find a place to park an extra vehicle if we had one. We use state parks a lot, and we routinely see an overflow parking area. You could park the truck their and keep the car at your site for daily use.