How do I "break-up" with a toxic friend?

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Question:  Dear Social Shrink: I am friends with this one girl who I believe to be toxic to me. I say "believe" because she hasn't done anything exactly to create a falling out between us. We have been friends for years but more recently, I feel like she's been using me. She asks me for rides just to get her from one place to another, expects me to pay for certain things, makes plans with me then cancels last minute which I later find out she went to hang out with other people. I already told her some of these things annoy me but she is in complete denial and comes up with excuses for why she did these things. I don't know what to do and tried hanging out with her less but I find myself continuing to end up in these situations. Help! How do I break up with a friend? (San Diego, CA)

Social Shrink:

Hi There,

Breaking up with someone in any kind of relationship is always hard. It's good that you already told her how you feel but make sure she understands that. Maybe she doesn't know what she is doing and that's why she is in denial. However, if you believe her to be doing these things maliciously then she is definitely a toxic friend. 

How do you know she is doing it maliciously? Well, you pointed out to her the things she's done. Do other people notice these things or is it just you? If she does this to others, it may be just her personality and that certainly needs to change, but being the good friend that you are, you can help her with that. For example, next time she asks you to pay for something, ask her to split with you or let her know you paid last time and it's her turn. Try setting boundaries with her to let her know you can't be used.

If you think she is doing these things to just you then she probably knows you are someone manipulate and continues to do it. For you own self-respect, don't let her do it! Again, it's hard to break up with someone but you shouldn't let that stop you from being around a toxic friend. Let her know, you noticed these things and until she changes, you cannot hang out with her. She might still be in denial but you should probably give it some time before hanging out with her again, if that's what you want. She needs to learn that people should not be used, especially friends.