2am feeding sessions are destroying me

My son is 3 weeks old and I feel like I'm losing my mind. My wife is breastfeeding but she's so exhausted that I'm doing all the diaper changes and trying to help however I can. Last night I was up from 2 to 4am just holding him while he fussed. I know this is temporary but man I don't remember the last time I slept more than 2 hours straight. When does this get better? Any tips for surviving this phase without completely losing it?