Does a woman experience occasional bedwetting when she reaches her mid-forties?

No.  Time for a trip to the doctor.  There is medication that should help you with your issue.

Ditto what Harry said.

I would say go to the Dr as the others said. 
I only had that happen once while I was pregnant....20s not 40s.

Hi.  Might this be averted by taking less fruit, liquids, sweets in your diet?  Or increasing intake of foods naturally contractive - like whole grains, root vegetables, salt?  Even relaxed our body should have the naturally constrictive abilities that prevents this. But as we age even in good health we start having less control - has not yet happened to me but I am afraid it will  and as a result have begun making more frequent pre-emptive bathroom trips in the last few years.  And my husband is starting to have the beginnings of it.

ive never had that happen, i usually will wake up if i have to go, if that happens maybe you should wear a diaper to bed so you dont have a mess, also, go see a doctor to find out why its happening

From the internet---site can be found by highlighting the italicized paragraph and searching for it.

Causes of adult bedwetting can be both physical and psychological and may include diabetes, bladder cancer, neurological disorders, side effects of medication, prostate cancer or enlargement, urinary tract infections or urinary tract stones, and obstructive sleep apnea. Other various causes of adult bedwetting may include acute anxiety or emotional disorders, a small bladder size, and constipation. Hormonal imbalances can trigger bedwetting in some people. Many hormonal problems are caused by adrenal or thyroid dysfunction such as in autoimmune thyroid disease, Hashimoto’s disease, and hyperthyroidism.

Your parents were right, It happens sometimes but it shouldn't.. I suppose this is an older post and by now you must have consult a doc.