Why do I keep getting hacked?!?

[L]

My World of Warcraft account got hacked, my Twitter account got hacked, my Facebook account got hacked (twice), my AOL account got hacked, my yahoo account got hacked... I've looked at the reasons on why they hacked my account and it all seems to be for spam use. My passwords are always complicated and have a capital letter in them and at least 1-3 numbers. I don't make my passwords simple like my dogs name or anything like that. I did a virus scan to make sure I got no Trojans or keyloggers, I did everything I'm suppose to do but for some reason I keep getting hacked... And it's all for one reason, to spam my contacts and advertise their stupid product. This is ridiculous... Is anyone else having a problem with getting hacked lately?
I'm also using Avast, did a virus scan 10 times now and it hasn't caught anything.
I'm so confused.
So if I have Avast and Malewarebytes will they conflict with each other?