I am a lot like you. I am very frugal by nature, and my wife is more spend thrift. $1200 a month seems excessive to me. However, you did mention a key phrase: on her credit card. Is this a joint card or is her card solely? If it is a joint card then you have every right to ask about it, and even to check out the charges online.

If it is her card solely, then just let it be.

My wife accused me of being controlling with spending on BD. And there was a bit of truth to it. I 180'd on it, however if I were to see excessive spending I would at least ask her about it, in a non-controlling, non-accusatory, and non-threatening manner.

M(53), W(54),D(19)
M-23, T-25 Bomb Drop - Dec.23, 2017
Ring and Piecing since March 2018