I'd have to say i'm a competitor and mechanical type. I love driving. I'd be doing real cars if I could afford it
. But I love working on my car during the week, cleaning it repairing it, putting a new setup on it. I've managed to gain a good friend since i've been racing and we push each other to get better. So when you say your brother and friend stop I can understand not feeling motivated. If I didn't have my buddy there it might be a different story.
I typically go to the track on a Friday night for practice and then racing either Saturday or Sunday depends on the time of year. Going to practice keeps me sharp and ready for race day. the lessons learned on practice days have made me better come race day because I've learned to quickly drive around pile ups and pass slower cars. Not to mention learn the fast way around the track.
I've been racing a year and a half but i've been in to RC for 17years. So I'm not quite at where you may be, I'm still learning everytime I go, which makes it enjoyable to me. I still count the days till I can go to the track again.
If your not motivated to drive then don't. If you can still perform on race day and be happy with the way you perform then good for you. Now me on the other hand if I do crappy one weekend I know I'm going to try to get more time the following week, if I do well but know I could have been better then I still know i'm going for more track time and possibly a new setup to get to where I want to be.
Do what you have to do to be happy, that's what a hobby is for your entertainment.