Sounds like you have capital D Depression.
Gaming and building a new sick PC is very very very fun. If you aren't having fun engaging with something inherently fun that you used to enjoy, you're more than likely experiencing clinical depression. Anti-depressants suck. Do your shadow work and find the cause of your depression, then crush it with all your might and focus on the positive side of life. Your hobbies may not come back to you, or they might. Whatever happens, your life will improve over time.