I say go with the flow. With DS1, I battled to get him in bed for around 7 o clock, most nights ended up there with him until 9 or 10. Did a lot of rocking and pacing. It was rubbish spending all evening trying to get him to sleep. Wish I hadn't bothered, he wasn't a creature of habit and routines didn't suit him or me.
With DS2 I decided that to preserve my sanity he would stay downstairs with me until he's properly conked out. He usually falls asleep around 9 but sometimes it's a bit earlier, sometimes later. He is also a crap napper, has one long sleep at some point in the day but generally grabs half an hour here/ 10 minutes there sort of thing.
I am not a go-with-the-flow kind of person but the main advantage is that I now don't exhaust myself trying to get DS2 to sleep at fixed times. If he looks tired, I try to encourage him to sleep but that's all. I know routines work really well for some but for me, every day was a big FAIL and made me feel like I was rubbish at being a mother.
I try not to have any expectations with nighttime sleep either. He started sleeping for 7 hours, until 4 am or so, a week ago, having a feed then back to sleep until 8 or 9. DS1 didn't sleep through until he was 2 so that, to me, is miraculously good. He started on another growth spurt yesterday though and fed a lot in the night but that's fine because I thought he might. Shattered hopes when you are sleep deprived are hard to take.
Having tried both, I'd choose spending some time with your DH, actually having an evening and letting her tank up for the night. She may well go back to longer sleeps.
Good luck whatever you decide, hope you're getting some more sleep soon.