Absolutely, leaving Canada for any amount of time and re-entering will reset your 6 month visitor status ( Unless they stamp a specific end date, which seems to be rare for visa-exempt countries)
I am so sorry your friends gave you horrible advice. Granted, there is no guarantee you will ever be allowed entry into Canada, but as long as you say you are visiting, have bank accounts and things in the US, you would have probably been fine, despite spending the last 6mos in Canada. Lots of people travel back and forth over the border while waiting for an Outland app to finish while in Canada w/ their spouse. Once you have a PR app in process, they seem to be more understanding, esp after Sponsorship Approval, about border crossings.
However, I can't say now that you have over-stayed. They will see that you over-stayed your 6 mos in Canada and you are very likely to be denied entry.
I'm going to let a senior step in with more information, I don't know too much about applying while out of status. AFAIK you can still apply Inland, while out of status in Canada (as you are). However, Inland wait times are extremely long, much longer than Outland (7-10 mos vs 2-3 years), however Inland is eligible for OWP.. but, my understanding is that you're not eligible for the OWP pilot if you are out of status. And if you were to apply while out of status, and were to get deported, your application would be done.