I can't tell anyone what to do. but being generally nice to most people doesn't feel like a difficult ask to me.
Don't even waste your time arguing with these troglodytes.
Obviously, we know you had good intentions, but since douchebaggery is kool and trendy (one need look no further than Trump), douchebaggery is what you shall receive.
Now, for the record, a smiley face/emoticon after a "rude" statement is a signal to the reader, from the author, that they are not 100% serious.
So, this needless drama stems from a misunderstanding.
RECAP:
(1) misunderstanding
(2) douchebaggery
(3) repeat