If you're like me, deciding to stop checking a site is one thing, but actually following through is another. Help yourself break the habit of checking a site by blocking it from your phone entirely.
This method is often used on computers but I don't think many people are aware that it can be done on Android too (if your phone is rooted).
Use this app to edit the hosts file, adding an entry for 127.0.0.1 / www.reddit.com
It will take a few minutes to affect your browser, but after the IP is re-cached you won't be able to load anything from that site anymore. Also works for preventing ads or data reporting if you're more crafty.
The problem with host based blocking is that I'll just unblock it when addiction sets in. For it to work, I can't have access to the device filtering me. For me to work in general, I have to have access to the device filtering me. Plus proxies, VPNs, Tor, etc can get around them even if it were a standalone device I couldn't control.