Windows 10 automatically applied Helvetica font to programs

I recently installed a font called Helvetica Neue on my PC so I can use it in Photoshop. After installing it, it appears the stupid OS decided to automatically throw it into Google Chrome and Firefox displaying the font in all major websites such as eBay or Facebook. It has become annoying, and it's definitely a non natural feel. I've tried the extensions from the Google store to change it back to normal but it appears that the text settings have either Times New Roman or Arial installed, there's no sign of Helvetica. I really don't want to reinstall windows again, I never did anything to the OS other than dropping the font files onto the Windows's Font control panel. How do I get rid of it as deleting it would tell me an app is using it, and when there's no app using it pressing delete does nothing at all. It feels like a virus!

Another reason to dislike Windows 10

Thanks for your reply, as I said, I've tried all the steps to revert it including the obvious Chrome font settings. But why would both browsers be affected if it wasn't Windows? It was DEFINITELY Windows 10, after a restart, I was able to exit all programs running in the background and then remove the stubborn Helvetica Neue Thin font. Another restart later, both Chrome and Firefox are back to normal.