Myself and mortified are AWFUL. I also can’t stand when someone says she invited less people to her wedding, or that there were less trees on the property after a neighbour cut them down. It’s FEWER, not less!!!
Fewer is used when referring to individual things that can be counted. Less is used when referring to singular mass nouns. For example, you can have less salt, time, money, honesty or love. You have fewer grains of salt, hours, pounds, lies, relationships, people, or trees.
I know all the mis-users will say they don’t care and it doesn’t matter for them. But you have no idea what opportunities, relationships, conversations, and connections you forgo when you present yourself as uneducated and lacking decent communication skills.