You don't have to click on mobs at all. In fact, just let go of the mouse entirely and your life will become much easier. Target with TAB and F9 and use hotkeys to access abilities. You don't have to separately initiate combat, just use a hostile ability and it'll start auto-attacking whatever you've targeted.

If you only have one class at 22, you might not have that many useful abilities. At some point, however, you'll be almost constantly using something or you're doing it wrong.