Contact your local Department of Social Services first. There are many advocacy programs for the aged that can assist you and your efforts.
They can also point you in the right direction for other outside resources.What do i do if i am conservator or my parent that is hateful, uncooperative?
In order to get in to see your parent, call local law enforcement (local police or sheriff office) and ask one of them to meet you at your parent's house. They will have a way of getting inside. At least that way you can check on her status.
Then report the situation to your local ombudsman or Adult Protective Services. Ask them for their recommendations. I suspect that they will suggest that you relinquish your conservatorship in favor of an independent third party.
If you are unable to come up with a resolution pretty quickly and the situation continues unresolved for more than a couple of weeks, file a report with the court detailing the situation and asking the court for instructions.
Doing nothing is not an option because you are personally responsible for any adverse consequences.
I don't know what state you are in, so this posting is not a substitute for advise by an attorney admitted in your own state. I am providing this for general purposes only. Paul Deloughery (email@example.com; www.delougherylaw.com; 602-443-4888; www.azprobate.blogspot.com)