I [27F] want to divorce my husband [29M] but he doesnt believe me.

Some background: I met my husband as a rebound out of my high school sweetheart relationship. Everything was super intense and we quickly fell in love. Within a year he had proposed and I accepted. We've been married for 2 years and together for 7. At some point in the relationship, without my noticing, we became best friends instead of lovers: at least on my end of things. We even stopped having intercourse about 4 years ago, not that we weren't sexually active with one another, we just weren't having intercourse. Our sexual encounters were also spaced out at maybe, a hard maybe, twice a month. We never planned having kids or furthering the relationship in any way, either.
Around 6 months ago I had a very close friend finally grow a pair and ask me why I allowed my husband to change my personality so much. I was really confused for a few weeks but then I started to realize how true this was and just how miserable I had been in the relationship. I had been morphing myself into someone else to make him happy and to allow the relationship to work. I wouldnt argue with him, I always agreed with him, I was quiet around him, I never partied and harder than a beer, the list goes on. So I started looking into things: alimony, lawyer cost, etc. and further and further down the miserable rabbit hole I fell.
With this, I started emotionally cheating on him hard core with someone who allowed me to be myself. She was a close friend to begin with and the transition was thus easy. With her I came full circle to see that the life I was living prior with my husband was all a lie clouded by a busy schedule, the desperate want for a picket fence and 2 kids (again, not that we ever made these kind of plans), and the familial pressure to have a happy nuclear unit between us.
My husband caught us, in text messages, about a month ago. I finally came clean about everything I had been feeling for the last 6 months....and he didnt believe me.
Fast forward, Ive been living with my grandmother for the entirety of June and have told him that I want a divorce and he.... still refuses to believe me. And whenever I bring it up he flies into mental breakdown mode, that he was a fool to drive me to emotionally cheat and that he will do anything to get me back.
But I dont want to go back to living a life I was unhappy in. The entire construct of the marriage was built on guilt, peer/familial pressure, and the belief that I had "Achieved everything in life".
Does anyone have any advice on how I can get him to believe me? I live in Ohio which is a no fault state so if I have to I can apply for a no-fault, uncontested divorce but Im worried if I do that that he'll still try to cling onto me.
Tl;dr My husband wont believe that I want a divorce and I cant think of how to convince him I do and I dont know that he will leave me alone even through a no fault uncontested divorce. Any advice on how to convince him?
Edit: some pertinent information. He's dealt with severe depression and anxiety for the past 3 years and the biggest reason I want him to see WHY we don't work is because I'm terrified of having someone's mental ruining on my hands. I'd be fine just serving him otherwise.


Source.