How to balance a regular sleep schedule with showing up for my (30M) wife (30F)?

(sorry if this duplicate posts, I’m still new-ish to reddit) This has been an ongoing issue that comes to a head every few months or so. It probably will seem super silly to most people, but for some reason we’re just stuck on it, so any \*helpful\* advice will be appreciated. Also, before anyone suggests divorce, we’re not going to get a divorce over different sleep schedules. We’re also already both in therapy and couple’s therapy.

TLDR: I (30M) go to sleep around 10:30 most nights, wife (30F) wants/needs to stay up and talk, sometimes it’s about really heavy things that she’s dealing with. How to balance a regular sleep schedule with showing up for my wife?

I tend to go to sleep around 10:30 almost every night. My wife (30F) says that that’s “really early”. I don’t choose to go to bed then, it’s just that I know my body and that after 10:30 I’m basically useless. Everything shuts down. My wife tends to stay up later, anytime between 10:30 and 12:00, or even later if she’s chatting with friends in a different time zone. I have no problem with this. I’m usually so far gone by the time she comes to bed that I don’t even notice her come in. The issue is when she asks me to stay up late to chat with her. Sometimes it’s just for a chat, sometimes it’s because she’s having intrusive thoughts and big feelings. I’m okay with sitting up with her every once in a while, but there are times when I simply can’t. It’s not that I don’t want to, it’s just that there comes a point at night when a person can’t hold on to wakefulness any longer and for me that time is usually sometime around 10:30. If there’s an emergency like she has a panic attack or nightmare then of course I get up and be there for her even though I’m not functioning at 100% or even 50%.

We’ve tried adjusting my sleep schedule to go to sleep later and always what happens is after about a week I’m miserable, can’t focus during the day, nodding off at work, get sick, can’t sleep at night, and it usually takes me about a week to get back to normal. I’ve asked her if she can chat earlier in the evening (we’re usually together from 3 to bedtime on weekdays and all day on weekends/holidays) and she says that doesn’t work because she doesn’t control when the intrusive thoughts/big feelings come. I’ve also tried asking her to come to bed earlier (I’m usually in bed at 10:00 and reading or making notes for the next day) so we can talk then, but she needs that time for getting ready for bed (her nighttime routine usually starts anywhere between 9:30 and 10:00 and lasts 45 mins-1 1/2 hours). At this point I don’t know what to do. I want to be there for her when she needs me, but I also can’t stay up later every time she needs me to. Any ideas?