After ignoring several British ultimatums, in November 1878, British forces invaded Afghanistan.
Start discussions with, "How can we…" or "Would you consider…" instead of issuing ultimatums.
Everyone knows ultimatums never go well.
She told me that her husband gave her ultimatums and she has given him some.
This is a fair question for you to ask and would be a lot more helpful than what you have been doing, which is threatening to end the relationship and/or throw him indirect ultimatums.