0 lp struggle
Why am i getting demoted on losing one game with 0 lp? 
Why am i getting demoted on losing one game with 0 lp? 
have you tried winning at 0 lp?
You lost to many before that, youre division wasn't matching your MMR. Only way is to climb the ladder again by wins
Most likely because your MMR is lower than were your current rank is.
Because you have really low MMR. I lost like 6 games at 0 lp, and didn't demote.
It seems to me that you're riding on people saying "Tryndamere is OP" without considering that you need to learn your champion well to succeed.
I'm sorry to say it like this, but you haven't given me much to work with.
Unless you're talking about ranking mechanics, which I'm pretty sure it's always worked like that?