My poor husband was hollered at by me so often the first few weeks of parenthood. I just felt powerless and frustrated and he was the nearest person to take it out on. In the years since, I've often thought of how I could have avoided hurting our relationship.
1) Have a code word for "take the baby and leave me the hell alone, I'm going to blow".
If you've ever been in an argument with your partner, you know saying something like "ugh just go away" can be the catalyst for a full-out fight. Think of a neutral code word, like GALAXY, to yell out before your emotions get the best of you. Let your partner know (ahead of time) that this means you're irrational and are best treated with kindness and left alone, preferably with a snack (anyone else get hangry?).
2) Make a "what to do if I can't figure out breastfeeding" list.
Link youtube videos, infograms, phone numbers of friends/professionals who can help. Because at one point you'll realize you aren't prepared as you thought for 4am cluster feeding with nipples that are ON FIRE. If your partner starts throwing out random platitudes to try and "help" you're probably going to explode.
3) Prepare for the thirst
You are going to be sooooooo thirsty. Let 'em know, preferably before they need to refill your glass five times in 30 minutes. I've seen some hilarious set-ups, like a tote full of ice water with a tube for a straw, a camelback, or just giving you gallon jugs of water.
4) Tell them you're going to need your own bathroom
You think birthing is messy business? Try the week after birth. You can hardly stand up straight, you're trying to spray water on your hoo-haa with various devices, and you're probably wearing diapers. It's messy. Tell them you need your own bathroom and to just stay out of it for a few weeks. Once you heal up you can go on a cleaning spree.
5) Have a standing appointment to go out.
Alone. No baby, no partner. Just a time every week when you can shower, get dressed, and go somewhere by yourself. You really need this time to feel human again, and to remember that you're more than a mother. Even if you just go to Walgreens and look at greeting cards, it's something.