Minecraft singleplayer

Delete minecraft and all your maps and anything related to minecraft, etc.
install minecraft again from the official site only!
and all though you will lose all your maps and creations minecraft will work again, which is better than having a glitchy minecraft you can't play at all, if this does not work use a different mouse, if all else fails, move all of your files on your computer onto a external hard drive, reboot it, move then all back, if this fails too, then your computer is probably too old to play minecraft, and you'll have to get a new one, but really that is highly unlikely, deleting and then re installing minecraft should work, or it is just your mouse, change mouse and try it, then delete and reinstall minecraft, then reboot your computer.