I started to respond to the thread about justifying a .308 when one has a 6.5x55, but I decided this is a common subject brought up in many threads.
How do you manage your buying shotguns, rifles, and hunting trips, with your wife?
As with anything in life, there are better ways of doing things, how they should be done, and rules.
The first obvious rule is that one shouldn't spend money they can't afford, especially if it gets in the way of vital expenses and savings. But it is good to stretch a little sometimes, or, as we did as boys, dream and save money.
You should be in the open about it. It shouldn't become a problem between you and your spouse. But you shouldn't trade spending, her buying something because you did.
Don't act independently. Discuss it, and see if your reasoning stands up. And see if there is something negative going on with her that needs adjusting, some incompatibility that can be straightened out.
Ideally, you should do it by the principle of Enthusiastic Agreement, and be honest and open about it. That might mean selling an old car, or two unused pedestrian rifles in order to buy that one you think you will keep forever.
I have a friend who earns a lot of money, but was, for years, unable to buy a second centerfire rifle or another shotgun. He just tossed and turned over it. He and his wife were on a trip and stopped in a little town to eat and meander a while. He went into this gun store ( of course ), and called me from there, asking about a 1936 Winchester in pristine condition. I told him it was a deal. I knew the dealer. His wife came in, and they left. He told her about this rifle, that it was worth twice the asking $1500, and she said, "Why don't you get it? Reward yourself for all the work you have been doing."
That's the way it ought to work. And your wife can surprise you like that.
---- Freudian mistake: Got interrupted and typed "rife" instead of "rifle". Ha!