I think it’s a process of different stages.
Acceptance is huge and will help a lot.
Maybe the word abuse is still fresh and a bit scary, but read a few things on it and over time it’ll make more sense and maybe give you some comfort or reassurance that it has a label, it’s a real thing that seemingly lovely people do and your problems are not caused by anything that you’re doing.
Also accepting that this wasn’t the plan but it is what it is, nobody wants their relationship to end in this way especially a marriage that you thought would last forever, but sadly that’s how it’s turned out and again not for anything that you’ve done.
Time will be your friend on this one, time to accept, time to make decisions, time that it takes to adapt to certain changes especially after years and when a sad life has become a habit, and also take the time to mourn the relationship. It’s been a huge part of your life and maybe it’s made you who you are, you might grow to become a different person once you’re out of it.
Another scary word is divorce, don’t think about it straight away, just know that it’s coming eventually but that you don’t need to deal with it right away. Plan a separation, think of your options, it sounds cold but don’t think about his options or plans because you need to focus on yourself and your wellbeing.
Get your head around it all first, use your time and energy on planning what’s best for yourself. Stop trying to work out what it is that you’re doing to annoy him or how you’re pushing him. You’re not. It’s his way of saying it’s over without having to do anything about it. Take a different view on things, he’s not stressed with you he’s stressed that he can’t end things, or maybe he’s scared to or doesn’t know how.
Having to make a decision like this is usually the less of two evils, it’s hard but you don’t have a lot of choice, life’s too short. Focus on yourself and take your time.