Regarding selfishness, it's good to do chores, sure. Dutiful. But the kids you care for are not much mentioned. You may matter more to them together-as-a-couple than you have predicted. So perhaps you are not selfish but detached - from their emotions, and from yours. Just a guess, I don't know you, but are you perhaps too much Apollo and too little Dionysus? https://en.wikipedia.org/wiki/Apollonian_and_Dionysian
Because that might also be also leading to a passion-free partnership. Plus, if the problem is too much Apollo, your solution is going to add more of that, and worsen the problem.