A friend is getting paranoid. I am exhausted of being accused of bad intentions. She thinks people are plotting against her. It's draining me. What should I do?

From what it seems, you have tried your best to help her out of her situation but it's exhausting you and clearly not working. She may be experiencing some mental health issues but in order to be sure, you should encourage her to see a doctor about her persisting paranoia.

No one can deal with mental health issues by themselves. When things get too much for you, it's time to seek out help. You aren't giving up on your friend, by helping them find or suggesting they see a professional, but rather you are giving them the opportunity to get better quality help that you can't provide because you didn't spend years of training in Phychology. Professionals are trained to work with people of all mental health issues, be advised that not all click, or understand you, so if the first one does not work, dont think it doesn't work, it might be the therapist, so try another.

It sounds like she might need professional help. If it is as bad as you say, taking a break from being with this friend might be a good idea. It will probably be better for you and her. If a friendship is taking a negutive effect on your health, it might not be worth it. She might also realize that she is getting paranoid if she sees the risks of losing you.

It is a very tough problem to deal with when a friend is suffering from delusions. The best thing to do when someone is suffering from a delusion is not to feed it in any way– meaning, do not encourage or discourage this behavior. Simply listen to her. For example, if she says "I think that woman over there is plotting against me." The best thing to reply with is "That sounds frightening. What evidence do you have that she is plotting against you?" My therapist taught me these techniques when I would have paranoid delusions. The next best thing is to step back and practice self care whenever she is beginning to become overwhelming. After all, you're doing everything you can for her. It's okay to take care of yourself as well.