Yes, my marriage is like this. We've only been married five years (known each other very well for twenty years though) but we've had plenty of difficult life events in that time to test us, including a stillbirth. I fully expect there to be hiccups in future, but I hope we will continue to communicate well and generally handle problems without being nasty to each other.
The money sharing one I probably phrased badly. I didn't mean it all necessarily had to be in a single joint account, that's very specific! I meant that it's all considered joint money in the sense that it all belongs to both of you and you decide together how to spend it. Not "I'm the one earning so I'll give you an allowance while you're at home looking after our joint children. And yes you will need to buy the nappies from that."
I guess some of the disagreement probably comes from differing definitions of marriage. I think marriage means a promise to sincerely attempt to stay together for life, to share everything (life, love, hopes, dreams, money (which is the least important of these)), to put the family first, to be a safe space, among other things. That's why I mentioned marriage rather than LTRs... I think there is a difference between the two. I wouldn't share my money unless I was married either!
If you are not in a marriage which is a kind of joining of two people, and sharing everything, then yes, some of my points may not apply fully. No judgement at all! There are many reasons for getting married for sure, and the age at which you marry may also change things. I could have written all this in my OP but I didn't want anyone to grow old and die whilst reading it...
I don't think anyone needs to tick all the boxes perfectly to have a solid, functioning marriage, no. Yelling at each other occasionally can be forgiven and forgotten. Lying about some things. Communicating poorly and letting resentment fester. Etc etc. All perfectly workable if you're prepared to work at it. BUT I don't think they're the ideal, that's all.
I just wondered roughly how many people had a marriage which is (very roughly, simplistically) close to the ideal. I know there's a lot more to it than that, such as feelings fun and sex and loads more, but it was too much for a post on Mumsnet!