When I read your subject line, I thought it was about something else.
So . . . about your friend and her child.
Not necessarily in order of importance . . .
in some places, children continue to nurse,
for comfort, not for nutrition, until they are 4 or 5.
I know in this country this would be considered very unusual.
Probably most moms here have stopped nursing by the time
the child has turned 2, or maybe when he or she has started walking.
But each mom+child is different.
Are you asking because you want to help your friend?
Are you concerned that what she is doing is unhealthy
for her child and/or for herself?
It may be that she totally missed her child's signals/indications
that she was ready to stop nursing.
At some point, especially if the child is around other children,
the child will figure out that maybe it's not necessary any more.
Also, the mom may be using breastfeeding
as part of her birth control method.
===================================
I've read some of the answers, not all of them yet.
Ladies! Please don't yell at one another.
It's really not necessary.
Good grief!
Meanwhile . . . . if I understood S.'s request,
she was asking whether what her friend is doing is "normal".
Some of us answered that, in fact, it is "normal".
It just happens that in this country, a lot of people
choose not to do what is "normal";
they do what is culturally typical or what they think is right.
It's everyone's prerogative to do what they think is right.
Yes?
One more thing (Peter Falk, turning back) . . .
OF COURSE the mother has pleasure when her children nurse.
Once the difficult parts have passed by successfully,
nursing is one of the most pleasurable experiences ever.
Possibly THE most pleasurable.
I wouldn't make any judgments about whether a woman
"uses" nursing to avoid being sexual with her partner.
The hormones associated with nursing are contra
to the hormones associated with sexual arousal.
Really.