If it helps, the lovely sister at the maternity hospital (which I was in twice after having ds: when ds was born obviously 
for 5 days as he developed jaundice and needed light therapy and then 2 weeks later as I developed a bad infection from one of my cats, we think, long story 
and was on IV antibiotics for a week 
) told me that it was actually easier at c4 months than at 6 months or more because as they get older, they're doing more things so you will miss them more.
And that babies are perfectly capable of being attached to more than one person - in fact historically and anthropologically, that was normal, with other family members helping out.
So a good child minder, nursery or nanny will not cause any damage to the child, who will adapt and actually probably be more adaptable. Any "damage" is more likely to come from changes in the way that you deal with her - but I'm sure you'll love her just as much, so that won't be an issue 
Think of it purely mathematically: if she wakes up at the crack of dawn, you'll be seeing her for x hours in the morning and then again in the evening for y hours. And she'll be sleeping for z hours during the day. If you're breastfeeding, you get the best snuggle time (Can't talk from experience about overnight feeds as ds slept through from really early 
).
The other way to look at a nanny taking up 60%, even a 100% of your salary (after additional costs) is that it's a short term investment to get your career going again: in a year/18 months' time, you might be happier with the idea of a good nursery or childminder.
The other good bit of advice that my best friend gave me (her dh and she are GPs and they had 4 kids, the last one with special needs) was not to worry about missing "key" moments because what matter is the first time you see or hear that key moment. She had a nanny (I think over the years she went through 4 but the first still a much loved "aunt" and the rest are all still in contact) - but in Wales, that wasn't too expensive Her children are all grown up now and are well adjusted, confident young people (a doctor, a lawyer and a pharmacist and the 4th one was doing well in supported "independent" living pre-Covid but is back at home for the moment).
Another thing my lovely mum told me was that no-one can make me feel guilty and to have confidence in my own decisions.
I'm sure you will come up with the right decision for you , your dd and your dh - your own wee family unit.
Don't let others judge you - only you can work out what is right for your family unit.
All the best, whatever you decide 