Hi Sunshine
Oh poor you - I know how you feel because my average night's sleep is 5 hours of broken kip - and has been for the last 9 months (sometimes less, sometimes a tiny bit more, but rarely much).
All I can say is, although it's not ideal, my body's adjusted and I can manage fine, provided the total amount of sleep doesn't go much below 5 hours for too long. I might have a power nap (ten mins) during DD's first nap, but otherwise I don't get extra during the day and go to bed around 21.00 or so.
I don't have much caffeine as the quick fix makes me feel worse in the long run. Likewise I tend to avoid booze.
I would say the best thing for me was accepting that 5 hours is manageable and stopping myself stressing over the (current) impossibility of 7 or 8 hours sleep and just getting on with it.
It's knackering, especially if you have another child, but I agree with EinsteinsMum about doing stuff so you can at least chill out a bit during the day.
Try and make sure you have some fresh air and exercise every day and eat healthily - and yes, TTSP, TTSP...
You are not alone! HTH [hsmile]