How to use "matters" in a sentence

I do not consider it necessary, at present, for me to discuss those matters of administration about which there is no special anxiety, or excitement.

'Cosette,' he said, 'your happiness is the only thing that matters to me

There is nothing else that matters in this world except love.'

"Catherine," I say again, smiling, because she is all that matters, and I can rest now because I know that she is safe.

That's all that matters.'

So I said, "If the vicar and his wife are satisfied, that is all that matters." And she laughed and said, "Oh! But are they?"'

I know very little about medical matters, but it seems to me most likely that the Martians were killed by germs.