Parenting the biggest challenge I'll ever face...

Sometimes I wonder why my children don't take me seriously...I do follow through...Yesterday at the park it took me counting until 3 and grounding them from, coming to the park the next day, watching movies that night, and finally chocolate was enough punishment for them to decide to go...
Today, they decided to rub their pickle (they are girls and that's why I feel OK saying that), on the table... and after a warning, I took it away...
For bedtime, I told Kyrsten if she tried to push her sister of her bed (yet again), I would stop reading...and so I did...they decided they didn't want to go to bed...first time I said I'd close the door...second time the light...and that did it...but geez...aren't they used to the right way of doing things by now???
As I type...Olivia has taken one hour to fall asleep...
Maybe they are sensing how guilty I'm feeling lately...Of feeling happy they are growing up and they can do so many things by themselves, while I do chores around the house...I feel super guilty...as if because of being raised by a single mom they won't get as much attention and they will have to grow up quicker...They deserve more than that...they deserve as long of a childhood and as much innocence as possible...extra if that's available..They deserve everything...and I wonder if even as I do my best every day, that won't cover it...How hard...And they bring me more joy, knowledge and lessons than they will ever know...how's that fair???
And I'm terrified of the world they'll face...keeps getting crazier and crazier and I hope they want me around and want to ask me questions about any topics...
(Serenity Praise here)...
Parenting the biggest challenge I'll ever face...