As any parent will testify, sleepless nights caused by a crying baby can put a strain on the relationship. But research claims it is the prime reason for as many as one in three divorces or separations.... 30 per cent of those who had split up blamed sleepless nights caused by their children. Some 11 per cent admitted pretending to be a sleep when their child woke-up so their partner would have to deal with them.The sleep deprivation that accompanies babies for the first three months is brutal. It's brutal for both parents, but it is particularly hard on the mothers, who are still recovering from childbirth and tend to be more sensitive to the child crying than the fathers. So, approach it the way soldiers do: if you have even 15 minutes of downtime, sleep. If she isn't doing anything vital, encourage her to go to bed and crash.
Adjust your schedule if you can so that you're already up to deal with the late night bottles; it's actually a lovely time to spend with your little son or daughter. I got quite a bit of writing done during those months.
Forget things you'd like to do, forget about everything except the absolute priorities that cannot be put off for a few weeks. Sleep comes first, her sleep in particular. Keep in mind that a sleep-deprived new mother is about as charming and reasonable as a demon-tortured soul in Hell; she desperately needs sleep and craves it more than the average heroin addict is jonesing for the drug. So make sure she gets it. If it's easier on her, it will be easier on you. This isn't about Game, this is about mutual survival. She'll also bond better with the child if she isn't resenting him for causing her to feel like a zombie.
Also, both parents have to learn to let the baby cry himself to sleep. Do it, and he'll be sleeping through the night months, if not years, sooner than if you let her rush in to settle him down every time he wakes up. And worse, neither of you will learn to distinguish between the "I'm going to cry for ten minutes and conk out" cry and the various other cries, which are not a uniform symbol of distress but rather an informative mode of communication.
It's important. It may even preserve your marriage during one of its natural stress points.