I really feel for you on the sleep - I have a non-sleeping child. She's now 7.5 and sleep is still not something she 'needs'.
Stopped napping at 6 months and even now she rarely goes to sleep till midnight. In the end we established a system where after 9pm it's mummy and daddy time - she doesn't have to be in bed or asleep, but she has to find something quiet to do on her own. So she does drawing or plays quietly but does not disturb us unless it's something important.
We literally tried everything including professional help and nothing worked so we gave up fighting and just adjusted.
In her case, it's possibly down to a hormonal issue - she has no endocrine IGF-1, which is a growth hormone, and it seems to effect her sleep and appetite, but it may just be her.
She never does the whole whiny 'overtired' child thing, but has vast amounts of energy. Even a whole day at school, after-school club, 2 dance classes and a 2 hr commute doesn't exhaust her, she bounces out of bed at 6.30am ready to go again. The only time she ever really sleeps is if she has a fever.
I had no help from family at all, and it's one of the reasons we only have the one child!
It took till she was about 4 before she had the resources to amuse herself for enough time for me to have some decent time to myself during the weekend and evenings.
It's really tough and exhausting, but it does get better and easier as they get older.