"But they interrupt me too"

In some households everyone jumps. You cut them off, they cut you off, and it evens out, and neither of you could say who started it.

The evening-out is an illusion, and I'd like to say why. Two people who jump on each other aren't having two conversations that cancel. They're having one conversation in which nobody reaches a finish. Both tails get lost. Both people go to bed with things unsaid. The fact that it's mutual doesn't halve the cost. It doubles it.

Someone has to stop first, and it doesn't have to be the person who started it. It has to be the person who's noticed, and the person who's noticed is the one reading this. Let them finish for a fortnight and say nothing about it. Two things tend to happen, in my experience. The first is that they don't notice at first, and then they do, and then they slow down, because a person who's being allowed to finish stops racing. The second is that they start letting you finish too, not because you've asked, but because the tempo of the conversation has changed and they've fallen in with it.

Don't keep a scorecard. "I let you finish, so you should let me" turns a habit into a negotiation, and negotiations about who talks are the least pleasant conversations there are. Just let them finish. The rest usually follows, and if it doesn't, you've still got your tails back.

A fortnight is enough to see it. Pick the person you most jump on and who most jumps on you, and for two weeks let every one of their sentences finish, with the hand-back when you slip. Don't announce it. At the end of the fortnight, notice two things. How many of their tails you've heard that you'd have missed, and whether they've started leaving you gaps. In my experience the first is always more than expected and the second happens more often than not, and neither required a word about interrupting.

If there's a child at that table, there's one more reason to be the one who stops. A child in a house where both adults jump learns that this is what talking is, and takes it to school and later to their own kitchen. A child who watches one adult start letting the other finish learns that the tempo of a room can change, and who changes it. The second lesson is worth having, and only one person has to teach it.