@Person125,
One of the best lessons I learned from my Dear Hubby was about ultimatums. My Dear Hubby's ExW is an abusive narcissist. She had the kids one weekend each month and we had them all the rest of the time (so 95% with us), and she has a very higher-ed degree--yet she paid no CS and claimed them each year on her taxes for a big refund. So I told him he had to stand up to her and claim them on our taxes or I'd leave him.
Now in my head (at the time), I was trying to communicate to him that this was EXTREMELY important to me and could be a dealbreaker--but what I actually DID was threaten him and try to manipulate him to do what I wanted him to do! WOW I never looked at it that way.
In a relationship, it is not reasonable to try to manipulate someone into doing what you want. Your partner is just as legitimate and absolutely equal to YOU. He gets to make up his own mind about what he will and will not do...and what he's willing to do or not. So giving an ultimatum doesn't work, because all it accomplishes is threatening the stability of your marriage in an attempt to be controlling.
I would recommend something more like this: "Honey, you are absolutely free to choose whatever you want to do regarding getting a job or not. However, I am equally absolutely free to choose whether I will support you with my earnings or not. I'm willing to reach an agreement whereby you contribute to the mutual work of our household at a level that is equal to my contribution to the mutual work of our household. But I am not willing to continue as we are now where I feel like I'm the only one contributing. So I've listed the bills and, from this point forward, I propose that we separate our cell phones into individual accounts, and that we each pay our own. I propose that we each pay our own car payments and insurance. Yes, it may be more costly but in the long run, I'm willing to be personally responsible for MY bills, and you get to choose if you will be personally responsible for YOUR bills or not. In addition, for the mutual bills of the household, I propose that I am responsible for A, B, and C...and you are responsible for X, Y, and Z (roughly equal amounts)."
Right now, he gets his cell, his car, his insurance, his internet, his cable, his electricity, etc. all paid for AND he's not taking on the role of a SAH spouse keeping the house clean and doing laundry LIKE IT'S A JOB. So no offence, but why would he want to change? He's got it made! He's brushed off his personal responsibilities and is being treated like a teenager. Treat him like he's an adult. Don't try to control him--instead allow him to experience the natural cost of choosing to not be an adult and contribute to the household.
Now one last word: in my personal family, I have 25 years of professional business experience, and my Dear Hubby does not. We quickly found that I could get a higher paying job, much faster than he could. [His skills are as a library assistant, for example--and that job just doesn't come up too often! LOL] So our mutual agreement as a couple was to switch traditional roles. I was the one who worked "outside the home" and earned the big paycheck, and he was the SAH husband. He was responsible for keeping the house clean, doing laundry, putting it away, preparing meals, grocery shopping and homeschooling our children (plus much more, but you get the idea). So you and your hubby can make any MUTUAL agreement that works for the two of you, and furthermore, if you enthusiastically agree to it and he enthusiastically agree to it, then it's not our position to "judge"!! But it should be MUTUAL--which means it works for BOTH OF YOU (not just him). Make sense? Maybe he just doesn't have the training and skill to get a job that pays as much as you earn. Okay that's cool--then he can GO TO SCHOOL to get trained! Or he can be a professional SAH who has a part-time side job to bring in some spending money. Or he can work from home and be part SAH and just earn less than you. The point is that as an adult, the contributions to "The Household" or "The Family" should be equal enough that there isn't resentment.