I told my client that I'm attending a conference and I'm out for few days.
He wished me well.
He then proceeded to write me messages and emails each day to "make sure" if I didn't work on his shitty website.

I can't do it anymore I'd love to finish this and ditch him asap...

Inform him that accidentally​ his mails got in the Spam folder.

If you know what I mean.😎😎

You told the client you were out so just ignore the emails until you get back to work, then just reply with a single email saying that you're back and give him a sitrep/reply to actual questions... Clients tend to be pushy and if they get away with it great, if they don't nothing really happens so just don't give in...