Dear god, I hate MP in this game. Whenver I reverse the hollowing to kindle a bonfire, I instantly throw myself off the next cliff to be left alone. Invasions are nothing but a nuisance.
There is an option at the bottom of title screen to log out and play offline or you can set the game to start in offline mode in the options if the MP bothers you that much...
This is bugging me - I haven't been invaded once, spend all my time in human form. If I have gravelord signs on the ground will I not be open to invasion?
I am in the same boat. I have only been invaded once but I had a +10 weapon before I killed the Gargoyles so I did not get much co-op summons either...