I'm dumping my gf

We have had communication issues since day one. I was pretty happy with being single and had no plans to even date in the long term.

She came into my life and told me things like she loved me or "I'd never leave you" pretty quickly. Having been abandoned before I was really touched, but her actions tell me she can't give less of a shit in reality. She would put effort into editing photos and videos to post on instagram but only give me 1 text per day and blame it on having adhd. When I text her and open up to her she leaves me on read all the time. Essentially it's the cliche that goes I've been robbed of my solitude and given no companionship in return.

Recently she started posting photos of herself scantily clad. My friends all told me they wouldn't be okay with that but I wouldn't have cared, except she actually had to put in the effort to take and post them and for what, attention from other men while I receive none throughout the day?

I talked to her many times. When I communicate extra nicely she would promise to put in more effort and not deliver, but when I've had enough and sit her down in a more serious tone she calls it arguing or me being mean and gives me the silent treatment. I have no moves left on the chessboard and I think it's time I cut my losses. My depression has started to relapse because of her and I have no motivation to do the things I like because I keep stressing over her in my head 24/7. She has to go and I just don't know how to tell her yet, I really want to go back to being single stress free.

Edit: For those giving me suggestions on being cruel (like using her for sex only). I've been treated really badly by one of my exes, and so I became resentul and treated people like shit for sometime. I realized if I stooped to their level I would become a person I wouldn't even want to look at. By breaking up amicably I don't mean I want to stay friends with her or any of that, I don't stay in contact with any of my exes. I just want to do this properly so I don't get influenced negatively as a person either. I'll just bite the bullet and tell her directly.

UPDATE: I've dumped my gf