I asked before why you are in such great pain. You declined to answer, saying you wanted to work on changing you in the present.
But, the bitterness, hostility, pettiness, anger, huge disrespect (funny you wrote about that last night because I was going to post about it yesterday), irritability, grasping superiority, judgmentalness, dismissiveness, withholdingness, condescension, and vigilant hyper-criticalness you have toward H floods every interaction you have with him. It also shapes every reaction you have to a suggestion or comment someone makes to you on this board.
Look, you say you want to work on yourself. Then do it. Until you address the deep pain you are in to get yourself into the place you are with H, not much in your life or your R will change.
Soooooo much of what you are reacting to in H is really all about you. Your interactions with H could have been mine with XH. It is VERY hard to see that so many of your issues with H are about things entirely different from what you think and many of the are just with yourself. While you are in such pain, you will continue to despise H.
So, again, why are you in such great pain?
And, I really think these would be great books for you:
Reinventing Your Life: The Breakthough Program to End Negative Behavior...and FeelGreat Again
Conquer Your Critical Inner Voice: A Revolutionary Program to Counter Negative Thoughts and Live Free from Imagined Limitations
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As for how to tell H you think he is an unmanly weak idiot and that he needs to change if he wants a thimbleful of respect from you, don't.
Instead, try treating him like a strong, manly, intelligent guy who you respect.
CV: H, it would be so great for me if you can install this shelf. H: Well, yeah, let me try. CV: Excellent! H: I dunno if I can figure it out, the diagram is confusing.
CV: I know — why can't they get better illustrators! Seriously, I trust you. I know you can do just as good a job as me, probably better. It is tricky and I'm not going to freak out if it isn't perfect. I really appreciate you trying and you can always pull me in as a second set of hands if you need one. Just let me know, and I'll be at your service. And, btw, it really turns me on when you fix stuff for me. Isn't that crazy, lol?
Give H a chance to shine.
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As for taxes, if he has said he is going to do them this year, let him and trust him to do so. Taxes can be submitted late. Forms can be amended. No disaster looms. Let him be. You can totally avoid putting on your controlling B hat. Indeed, eliminate it from your R wardrobe altogether.
Create emotional space for yourself so you can do this. Have a plan if it looks like taxes won't be filed by midnight. At 11:30, just say: "Hey, for my own sake, I am going to zap my tax stress and file an extension electronically (with a generous overpayment to make sure we're covered if necessary). Cool with you?"
Between now and 11:30 on tax day, IGNORE the taxes. H is doing them. They get done or they don't. If they don't, you have a plan. So, between now and then, LET IT GO. Say nothing to H about the taxes. If he asks for help with anything, help him graciously with enthusiasm. Be a good partner. If he is panicking about not finishing on time at some point, only then might you make the suggestion about filing an extension to get breathing room as a good partner. Otherwise, GIVE HIM SPACE TO TAKE CARE OF IT HIMSELF.
You don't need to nag or manage or interfere or disrespect him. No disaster will strike. Leave him be. Promise yourself that you will manage your own tax stress without taking it out on him. When you feel the urge to act, remind yourself that you have made a very conscious choice to grow here and to give H space to grow. It is your choice to do this and you made that choice for good reason. There is no reason to control or panic. Disaster does not loom. An extension is very easy to file.
Make crystal clear in a loving way that you are staying out of taxes this year. Surprise him with the tax software, a bottle of wine, his favorite treat, and a card that says: "H, it's all yours this year! I promise to stay out of it and not stress. Just ask if you need anything, otherwise I am hands-off. Thanks! You're the best."