Side laying latch

Any advice on how to get my LO to get a proper latch at night in bed during a side laying feeding? I find I'm so exhausted (5 wks old still feeds every 2 hours) i try to fix his latch a few times then just give up and usually end up passing out as he feeds. It's taking a toll on my nipples from the shallow nightly feeds however. Any advice for an exhausted ftm whose husband is deployed so doing it alone?