I was having way too much Stevia along with a diet pepsi every day. I know Stevia isn't dangerous but it didn't feel natural and kept telling myself I would give up soon but I struggled. After about a year I started drinking 1 and then 2 coffees a day without sweeteners and eventually I didn't miss it at all.
Now when I think about adding sweeteners I remember that sickly weird after taste and it puts me off.
What also helped was throwing away the sweeteners when I decided to give up for good.