Once i figured out how to RP, i couldnt stop, its addictive

Anyways, my character got into some pretty crazy plots and all of it was fun, and i pretty much couldnt see anything bad about any of it. Eventually however, i started to encounter a few things that eventually pretty much caused me to lose interest. I tend to try to stay on good terms with just about everyone, and i believe that IC is IC and just that, which incidentally leads me to my first point:
People taking IC OOC: This REALLY annoys me. Just because someone may play a bad character does not mean they are a bad person, etc...its so annoying to receive threats OOC, about an IC event or encounter. It kind of blurrs those lines and makes it difficult to continue the RP.
People criticizing others RP in brackets: Im guilty of this, once in awhile but I try to usually be constructive: for example if someone is standing next to me valiantly fighting off a clacker with his trusty lightsabre, i might remind him or her in a tell that thats a -bit- over the top. However, i have seen people be harassed to no end by extremely rude comments made in brackets. I think that everyone can always learn more, even those that wander around as self-proclaimed RP-Masters.
Turning on or off RP: I can understand sometimes wanting to just mindlessly slaughter mobs, or mine for awhile, instead of getting involved in some complex plot, but if someone greets your character, why not take two seconds and greet them back IC? THe other day my character went to the mine, she tried and tried to strike up a conversation, but it was like being among ghosts. Everyone just stood there and mined and not one person made a comment, even when she started singing about how the fellow in front of her direly needed a bath. Other times i have been in the tavern and someone will make a comment like "[My character is really dead, but im just here]". How does that make any sense? Now everyone else that may speak to that character is speaking to someone that is technically not there... o.O
I dont want to sound like im complaining, but those are just the major things that came to mind when i read this thread. After awhile, a lot of these things became more and more prevalent and it just became annoying to try to RP. I tried making new characters and starting more 'everyday' RPs, for example: Pohim the little shoeshine..but it just became harder and harder to find people to RP with. Now it seems like barely anyone will at all