As the others have said it's by no means easy but it works and you make it work.

DD1 was 15mths when DD2 was born and DP has been working 7 days a wk and at times leaving the house at 7 and not getting home til 8
I do have family relatively close but not close enough to help and i don't really ask, i found the 2nd time round a LOT easier though as you already have a bit more of a routine and are likely to be a little more relaxed about it all.

GL and i hope someone can watch DD for you so you an enjoy your birthing experience together!