Several things:

It still amazes me how some etymologies can be traced:[From Latin invius, from in- (not) + via (road).]

Can anyone "translate" the poem into today's English for me, please? How can somebody confide to do something? And what's oppugn?
"If nothing can oppugn love
And virtue invious ways can prove,
What may he not confide to do
That brings both love and virtue too?"
Samuel Butler; Hudibras; 1662.

Also: The rising popularity of "definately" appears to be inspired by the sound rather than the meaning.
Augh! How can anybody pronounce this in any way other than def-in-ATE-ly?? That 'a' changes everything.

Lastly: Purists might agonize over the "decay" of the English language, but the best way to handle language change is this: be conservative in what you send and generous in what you accept. In other words, be punctilious in your own grammar and spelling, but overlook others' solecisms.
Yeah, yeah; daggone it. I don't think Anu wants me to have any fun!