How do you deal with malicious people?

A few weeks ago I had a falling out with my “best friend” from college and I’ve been nothing but civil throughout this whole ordeal. Our friendship had always been very skewed because she has a strong personality and I, on the other hand, am very easygoing and laid-back – the peace-keeper in the relationship. We became friends junior year of college and in the 4 years we were close, we had never once had an argument, most likely because it’s been a long-distance friendship for the better part of it (we’re from different states and I’ve lived in a few different places since senior year of college for internships and work, so we haven’t been around each other a whole lot). Knowing that she has an explosive personality (she calls herself a “firecracker” and most people, upon meeting her, compare her to a chihuahua), I always found myself biting my tongue and telling her what she wanted to hear on topics like romantic relationships and the way she relates to people (according to her everyone is stupid) because telling her the truth would probably fall on deaf ears or, worse, cause an argument. Normally I stay away from people like her, but for whatever reason she and I clicked and became close. In retrospect, I realize that our falling out was imminent and it took me living with her for 3 months to finally reach my breaking point.

We haven’t spoken nor seen each other since it all happened, but she puts little indirect jabs on her Facebook that I know are about me and our “situation.” Now, I’m not one to care about what people think about me and I run away from drama and people who create it like it’s the plague. I’m very comfortable with myself and have some amazing people in my life, near and far, who always tell me I’m a great person. But her little jabs are so infuriating because I know she’s being unfair (and even racist in some of her posts) and the worst part is that her mother and 2 sisters (her only other friends besides me) keep making little snide comments as well. At first I removed them from my news feed and hadn’t looked at their pages in quite a while, but last night, for whatever reason, I clicked on my former friend’s profile and saw some pretty awful things that she’s posted since I last saw her page. I immediately unfriended and blocked her and her family from my account, but I’m still really irritated. I have this nagging feeling that just won’t go away.

I’m in a happy place (mentally and geographically lol) and I’ve worked hard these past few years to get to where I am and to be at peace with myself so I don’t want any negativity in my life. And being that this is the first time I’m having to deal with something like this in my 24 years of life, my question is: how do I not let this situation get to me when she’s clearly trying to rile me up?

Thank you in advance!