A money issue doesn’t just mean having none. It can mean that one of you makes a lot and one makes none or a little, unbalancing the ‘power’ in a relationship. When you were dating did you both try to pay equally for things? After you moved in together did financial responsibility shift to one person alone? Did things move from balance to imbalance? Did you talk about it or just let it happen because it was uncomfortable?
Are you living within your means or way beyond them? Address this. This is one of the biggest problems couples face - And they usually don’t want to talk about it. Does one of you like to have lots of savings, college funds for the kids and insurance policies and the other simply likes to have things when they want them regardless of cost? This has to become balanced. It’s not a fight of one being responsible and one irresponsible. It’s different personalities; one may be fearful and label it responsible. One may be free and fun and label it irresponsible. Don’t label it. Talk about balance.
Show each other the real financial situation. Maybe you have separate credit cards with balances the other partner knows nothing about. Maybe there’s a secret debt. Maybe there’s a secret habit. Talk about it or honesty will be compromised and the relationship will be undermined.