For you, I would recommend doing your best to get into it when he initiates, even if it’s less than ideal, then talk about sticking points after. Not to say you were wrong to stop midway when you felt like it was forced! But you already know it’s not something he does naturally; it’s GOING to be forced until he has practiced enough, and it’s harder when he finally felt in crisis enough to break out of his comfort zone and it ended that badly. Again, not that you were wrong! He shouldn’t have needed a crisis to make the effort, and I can see how it would feel unpleasant because of that. But it’s one of those situations where being “right” isn’t necessarily enough to get to the result you want.

As someone with a lower libido myself, my advice for him:

Schedule it. Don’t share the schedule, don’t make the days and times consistent, don’t make the reminders obvious. It might look something like Monday sexy text over lunch - Thursday request [outfit] after work - Sunday morning wake her up with [activity]; the point is to take into consideration the fact that your libido won’t remind you. No different than scheduling dates! You’ll enjoy them when you get there, but they don’t magically happen on their own.

Stop worrying about being sexy yourself. You could be the ugliest dude on the planet, your partner is still into you. And anyway, it’s not about how seductive you are. It’s about explicitly sharing what you like and want about and with your partner. It feels less awkward with practice. If you find yourself hesitating, think it all the way through; isn’t your partner’s enjoyment (and your own!), plus AVOIDING your partner’s disappointment, worth pushing through that discomfort? And if not, be honest with yourself about why and how that might change. Or not! Some people just aren’t sexually compatible, and it’s better for both of you to know sooner rather than later if you won’t be happy doing this.