I agree with your analogy of love being a choice and why perhaps our S's don't see that as an option for them...
I also agree that intimacy is also a choice...and I do believe that marriage can be a comfortable couple living together, who occasionally ML...but it can also be more...if you choose to make it more...
You see my H knows how to ML...he loves me...we are comfortable together...but I want more intimacy...right now he is having trouble with it being a choice...but you know what???...slowly, and little by little, I am reeling him in...I keep doing what I want to create intimacy...I share little tidbits with him from time to time...and I am seeing subtle changes...I just feel like all the other healing that H/we have had to do...that this too, will take time...