Hi OP, well done for sharing how you feel, very difficult to do. I know i have been there & felt exactly the same, as times still do. A perfect example i would push my twins in their pram when they were about 2 months or so & I would see other parents with more than one child going about their daily lives & thought they were crazy for having more than one child. Thinking this is the hardest thing I have ever done, why would anyone do it more than once!!!!
Unfortunately it turns out I was suffering with severe postnatal depression & aniexty.
But also as others have added being mother is bloody hard work (noone ever wants to admit this), its taboo & not something you discuss in the middle of a baby sensory class, etc. The change in lifestyle is dramatic & noone prepares you for this. If there was a job advert for being a parent, nobody would apply. Also having a baby in the middle of a pandemic-i cant even begin to imagine, the additional stress, changes to life/routine (mine are 2 years old so I didn't experience this).
These would be my suggestions to help you:
1st-I am of course not suggesting you have post-natal depression, but i would recommend you speak to your mental health nurse or gp, whoever you can speak to sooner & get them to refer you to the local perinatal mental health team-they may say who are you talking about. Not many people know about them.
www.england.nhs.uk/mental-health/perinatal/
They can offer you specialist support, talking therapies, medication (there maybe a wait)
From my experience Venlafaxine is the antidepressant which works for post-natal depression. Sertraline seems to be the anti-depressant to go to, but it made me worse. But some antidepressants can the first few weeks of adjustment.
Look into these support organisations
pandasfoundation.org.uk/
2nd-get as much sleep as you can (as already mentioned) sleep deprivation is complete torture. You need to catch up on loads, you've missed so much as a new mummy & the stress you've been going through. Its easier said than done. But if sleeping at home is not settling for you as baby is there, the guilt, etc, if possible visit family/friend & just say can I fall asleep in your spare room/sofa for the night. Or stay in a hotel (if finances allow). Partner can hopefully cope (again dont understand full situation, breastfeeding, bottle, combination of the two). Also don't put to much pressure to keep breastfeeding if this is situation & why difficulty to sleep (not to start any debate here on which is or isn't best), but healthy mummy is in my opinion more important. So maybe review situation here, discuss with partner. (I breastfeed & expressed for 8 weeks & in the end I just couldn't keep doing it, so much guilt at stopping-but it was the best thing in my situation).
3rd-get slowly back into your hobbies, when you are feeling low, its so hard to do, your mind says no!! But it is so important. E.g. horse riding is my thing & is had played a fundermental part in my recovery & feeling like myself again. Your partner sounds great & explain, show this reply & he will help. It is so tough for partners & you feel so guilty as your not spending every minute with your baby.
But you need to be compassionate to yourself. There is a theory could compassion therapy. New mums are not very compassionate to themselves, instead worried about everyone & everything else. But this is key, you still are the person you were before being a mum, you just have to adjust & rediscover how to balance this person with your new mummy role.
4th-dont try & be superwoman, you can't do it all - I am not very good at this one (hope the humor helps) but don't push yourself too hard, be kind to yourself. Celebrate the successes & take one minute/one day at a time (the amount of times people told me that - I was screaming inside thinking you have no idea). But its true, take things one step at a time, things will get better.
5th- there maybe a delay in the perinatal mental health team assessment/support. So look into counselling maybe an option (not sure regarding your finances & the ability to do this). Also if you are employed/ on mat leave a number of employers have employee assistance programmes which often includes 6 counselling sessions. So maybe look into this.
6th - give yourself time, all the above does take time
The reason I share this is I have been at rock bottom, to hell & back & I have come out the other side. Not every moment is sunshine as a mummy (going through potty training at the moment i can assure you of this) but i have a happy life balance the majority of the time, it does take a huge amount of work to achieve this. I have gone back to work (my boys love nursery & auntie/nana daycare), i got a fabulous new job (career development & promotion), two amazing children, i ride/compete my horse when I can - my boys love my hobby - although the majority of the time it is far from compatible. I appreciate my true, amazing & supportive friends & do things with & without the children. Holidays maybe more building sandcastles, than sunbathing with my favourite book & truly relaxing. Me & my partners relationship has been tested to the limit & so have relationships with family.
It is a difficult concept for people to understand, motherhood should bring so much joy. Unless people have experienced it themselves they will sometimes never understand & have true empathy.
I hope this helps. You are not alone in feeling like this, many mummys do, they just don't have the strength to share. Remember you shared because you wanted support, advice, etc & this is a big step. Sending big hugs xx