Dad of 5 years here.

For the first few months to a year, you're running in emergency mode. As dad's, we have the easier, but more frustrating end of the stick. It does get easier with time (or at least more rewarding!)

Right now, your GF has 1 job, to look after your baby. Your job is to look after her. The most critical bit of that, however, is looking after yourself. It's impossible to be her rock, when your own foundations are eroding.

Care for her:

• Time out and time management. Right now, she is likely pouring all of herself into being mum, leaving nothing left for herself, let alone you. Your job is to keep her off tilt with this. Make sure you schedule time for her time, or at least down time. Also, make sure it's explicit about it. An unknown amount of downtime is FAR less valuable than a known amount.

• Take the baby out. Do for a 60 minute walk with the baby. Let your wife know what you doing, and how long you'll be out. This gives her time to do things like have a bath, or watch a whole show.

• Kick her out of the house. Ring her friends and coordinate a time they can go out. Don't leave it as a surprise, but do present it as a fait accompli.

• Sort food out. Right now, she is burning calories FAST, as well as being stripped of minerals and nutrients. Do some bulk cooking. Your goal should be to have enough stuff in the fridge/freezer that you can just grab and eat, on those days. Some ideas are cottage pie, Bolognese, chilli, or stews. All are easy to make in bulk, and keep well.

• Give explicit nights off. Often overlooked, but the broken sleep is a BIG deal. If she's exclusively breast feeding, this gets a lot harder. If your bottle, or mixed, it is doable. Often you will feel taking turns is the fairest option. This can just cook both of you. Instead focus on giving her a coherent night's sleep. Let her know that you are on dad duty, and she can sleep though/go back to sleep when they cry. (As an aside, pre measured containers of baby formula were a game changer for me. The measuring part was the part that most woke me up)

Care for yourself.

As mentioned above, you must not forget about yourself. This is the easier part, so long as you remember. Just apply the same bits above to yourself. A few hours out with friends, a full night sleep, and access to goo, low effort food makes it a LOT easier to keep an evening keel. This lets you be the rock she needs.

Also take time to bond with your baby. I loved baby wearing (via an elastic fabric wrap/sling). Even cleaning the house is a lot more pleasant with your bundle of love cuddled up to you chest. Also, baby smell is what crack cocaine is a pale imitation of. Spend time, either just the 2 of you, or all 3, but you on "dad duty". Apparently there's little sexier than a confident, capable man, just being a good dad. 🤷‍♂️ Particularly to an overworked mum.

Once you have this flow going, it gives your GF time to be more than just a milk cow. Once she has time and energy to be herself, she will start to have time and energy for you. This is where your 'village' shines. Schedule date nights. It might be once a month, when nanny has the minion, but it's something. Remind yourself why you love each other. The rest will flow from there.

As I said at the top, you're both in emergency mode right now. That's ok, you'll get through it. Your old normal is gone. But with a bit of effort, your new normal can be even better.