I'm going to try and make this as objective as I can for my own sake really because I am trying to work out what I myself think. I'm not doing it to conceal which one I am. I'm really very conflicted about it.
A happily married couple live away from any close family due to a very specific job one of them I'll call person A does. They are the main breadwinner. The other one's job can be done pretty much anywhere. They work full time but the salary isn't enough to cover the household bills alone. I'll call them person B.
Person A is deeply unhappy in the place they do their job long term, although they love what they do. This isn't likely to change. The position is probably quite insecure at the moment, not helped by Covid, Brexit and long-term trends in the sector. Other places to do the job are very possibly more secure but not unaffected by these things.
Person B loves their job and also the place they work but, as said, would be able to get a similar position elsewhere (although obviously might not like the working environment so much). This is a relatively new development.
They have two children who are very happy and settled with close friendships etc.
Person A has the possibility of a job elsewhere. Person B has always been supportive of their applications elsewhere because of the unhappiness. But suddenly everything is somehow coming together for the other three people involved and they are very happy.
How do we work out what to do, given that staying means one person will be unhappy and in a job that might disappear (this is far from certain but they are the main breadwinner) and going means three people's happy lives would be disrupted (although they may well adapt somewhere else).
What's the right thing to do?