Is dropping to part-time an option? I had my 5th baby a little over a year ago, and I dropped to a 0.5 FTE. I love it!! I work my five shifts in a row every two weeks, get to do what I love, and then I have a 9-day stretch when I can do the stay-at-home mom thing. I feel like it's the best of both worlds.
Unfortunately your hours are not specific to CVICU. 12 hour shifts are long, and leave us precious little time with family on the days we work. (My last job was 12-hour day shifts in an LTACH; I'd come home beyond exhausted and mentally wrung out, and the second I walked in the door it was "Mommy, Mommy!!!" I was happy to see their smiling faces, and they were happy to see me since I'd left before they got up...but then it was their bedtime. Between staying to chart and my commute, I'd frequently get home at 2100. All that to say, I get it) 8 hour shifts means we have fewer days off. But that's true for nursing in general.
The mom of one of my oldest daughter's friends works from home doing case management for an insurance company; she had worked in an allergy clinic, but wanted to be home w/ her kids. I can't imagine it's easy actually getting work done with babies around, but she makes it work.
Big hugs, mama. I know it's hard!!