Shimon Nodel,
“I explicitly said he should learn to love her or else leave her (for her sake) because staying would only bring her misery”
Your actual words were “or else consider finding a different wife he can love”, which is a different statement entirely. If a man cannot fulfill his obligations to his wife due to a personal deficiency, he must work on that deficiency. Simply ditching one woman for another will fix nothing. He’ll just carry the same flaws into the new marriage.
This was my point in asking the original question: I think we all agree that marriage is holy, and everything should be done to protect, uphold, and strengthen it, and it should not be just cast away. Same with learning Torah. If learning is boring or challenging, move mountains to make it better, don’t just ditch it. The yetzer hara goes after our most holy endeavors – it makes us focus on ourselves rather than our spouses in our marriages, and brings boredom, distraction, and frustration to our learning. Where the yetzer hara fights us hardest is where we have the best opportunity to do something meaningful, and that is where we have to stand our ground.