Hi, just to say cluster feeding doesn't last, but my gosh it's hard while it does last. My little one is four weeks now, and in the first week we had a couple of very heavy days and nights of it, but it did slow down eventually, and by the end of the first week it was easier. As I said he's 4 weeks now, and I got a good six hours sleep last night in two three hour chunks. We do have bad nights when he has a growth spurt, but it is getting better. And feeding is a lot easier too, he's latching on and feeding quicker, so I'm not sitting there for ages trying to stay awake. Hopefully you'll start to see that soon, with your little one.
The best thing you can do for your wife is to make sure you're fit enough to care for her and baby which means you need to get some sleep! Make sure that where she feeds has everything she needs, snacks, drinks, reading material, tablet, whatever she needs. And once she's settled and feeding, get some sleep. I also have a little lamp covered with a scarf, so I'm not sat in pitch darkness, which makes it easier to stay awake. Also during the day, you might need to be firm with your wife, if baby goes down for a nap, pack her off to bed for an hour or two. I really struggled with doing that at first because I didn't want to leave baby with DP, but now I nap like a professional, and he's a very hands on dad, it means he gets his bonding time too. Occasionally we both go back to bed when baby sleeps, if we've both had a bad night, so don't forget that's an option!
Good luck, it will get better I promise!