I think you should do the right thing and get rid of your family.
You don't need that kind of negativity in life.
I'm joking, ofcourse. I was in the same boat. I'm 25 and I got my FR-S last month. I still get comments from the family sometimes that I didn't do the most practical thing but I simply couldn't bring myself to liking any other car. The more I researched about the FR-S, the more I ended up liking it. So if you really like the car, you should go for it. Your family will get over it eventually.
It's a really nice car.