I agree with Bigsissie, If she's using a vibrator regularly, she probably won't be able to orgasm through sex or manual stimulation. She's trained her body to respond to a much much more intense type of stimulation.
Go to a adult shop and get a vibrating **** ring. That basically turns you penis into a vibrator or check into things that you can put on. Her use of the vibrator may have caused her to be less sensitive over the years so you should not feel bad. The constant vibrating can desensitize the nerves in and around the vagina It may be worth asking her if she could stop using it for a while before you get home. Best of luck.
Sissie