Tricky one indeed!
Like you, I have a formula for such situations and people:
1. Accept the situation/decision/action
2. Attempt to change the “perpetrator”
3. Walk away..

As you say, your lease probably dictates that 3. isn’t an option…unless you’re really strong, and willing to take a financial hit.
Sounds like you have tried 2…..and failed
So, looks like you are stuck with option 1.

However, to ease the pain a bit, you could:
1. Try to understand where the landlord is coming from…even if you don’t agree with him
2. Perhaps try and change your perspective or beliefs…seeing you have to live with it anyway. May as well go with the flow as fight it all the way…the only person who looses, that way, is you.

No easy answer, I’m afraid.