I have a suggestion. Rather than trying to figure out the exact right words to say (there are no such magical words), and rather than going on and on and on until another year goes by, why don't you start by doing one thing? Actually take an action. YOU...not him.
For example, today why don't you research divorce attorneys in your area? Today start making a list of all the divorce attorneys you can find within X miles of you. Write down their name, address, phone number, and a little bit about them that you can find online or in the phone book. Work on that today and tomorrow until it's done.
On Sunday, look at the list and pick your top five. Do your best to pick consistent criteria like you prefer a lady attorney or someone who's been at it for many years, etc. Just pick five you like the most.
Then on Monday start calling them and find out if they do a free consultation, see if they will tell you their fee, etc. Interview them as if they were applying for a job, because they are! The job is to be your lawyer! Find out more about them.
Then on Tuesday, find the divorce laws for your state and start reading them! STUDY them! How does your state calculate alimony? What's the process in your state? Knowledge = power to learn about it.
See, sitting still at home, doing nothing but expecting to find magic words that will convince him to divorce you but not hurt him...is not gonna happen! That's not reality! And it will slowly drive you insane because you are doing the same thing but expecting a different result. If you want the different result, you have to actually DO something different.
So pick ONE step and actually do that...TODAY. Then pick another ONE step and do that tomorrow. Slowly the steps will result in moving forward.