I'm not going to spend time with my family after work.
Do you have any problems with your family?
No, but I want to spend time on my hobbies, reading, and other things.
If you're working hard, it's fine to take some time for yourself. You can let your family know that you are busy, and that you care about them, but aren't available at the moment.
I think it's my right to spend my time how i want after all
You are within your rights to want to spend time pursuing your hobbies instead. You do not have to spend all of your free time with your family members if you do not want to.