...just take it from me, they're not just killjoys - they're wrong.
Once the baby's arrived things may seem tough to an outsider - but you have the benefit of being your baby's one and only mummy, and you may well find you have a slightly different take on things. (Were they not just being a bit envious?) You really love your baby, your baby more and more perceptibly really loves you, and the rest of your life picks up wonderfully from the day you leave the hospital. I haven't had a sad day since my baby was born 8 months ago (and I used to get horribly low on occasion). And my baby is one of the ones that never sleeps and wails if I leave him to go to the loo, so this is me even without a social life.
Apologies to those who've had PND, but just felt I needed to post this because I had so many of the above comments from an older - clearly weirder - generation that I had to correct their negativity for the first-timers.