Margaret Atwood

So another poem that my teacher told me to look at, out of interest because she thought I would find it interesting,

In the secular night you wander around
alone in your house. It's two-thirty.
Everyone has deserted you,
or this is your story;
you remember it from being sixteen,
when the others were out somewhere, having a good time,
or so you suspected,
and you had to baby-sit.
You took a large scoop of vanilla ice-cream
and filled up the glass with grapejuice
and ginger ale, and put on Glenn Miller
with his big-band sound,
and lit a cigarette and blew the smoke up the chimney,
and cried for a while because you were not dancing,
and then danced, by yourself, your mouth circled with purple.

Now, forty years later, things have changed,
and it's baby lima beans.
It's necessary to reserve a secret vice.
This is what comes from forgetting to eat
at the stated mealtimes. You simmer them carefully,
drain, add cream and pepper,
and amble up and down the stairs,
scooping them up with your fingers right out of the bowl,
talking to yourself out loud.
You'd be surprised if you got an answer,
but that part will come later.

There is so much silence between the words,
you say. You say, The sensed absence
of God and the sensed presence
amount to much the same thing,
only in reverse.
You say, I have too much white clothing.
You start to hum.
Several hundred years ago
this could have been mysticism
or heresy. It isn't now.
Outside there are sirens.
Someone's been run over.
The century grinds on.

Is there a much deeper meaning?