GRENOBLE, France — In her sexual fantasies, she is a fit and impetuous blonde who dominates her male partners. In real life, she is a virgin who relies on an electric wheelchair, her body touched only by home care aides and medical personnel.

“A disabled person is seen as a child,” said the woman in the wheelchair, Laetitia Rebord, 31. “So inevitably, child and sex don’t go together.” A translator and teacher, she has a genetic spinal muscular atrophy that has left her entirely paralyzed, except for her left thumb and her facial muscles.

Ms. Rebord, who says she feels physical sensation acutely, has looked for sexual relationships through friends of friends and men on dating sites and even with male escorts. But her disability has scared many away, and she says she is now ready to pay for sex in Switzerland or Germany, where so-called sexual surrogates are legal.

Stories like Ms. Rebord’s are far from unusual in France, where behind a facade of sexual freedom, disabled people struggle to have a sex life. But their desires are often disregarded, and while prostitution is legal here, soliciting potential clients and serving as an intermediary between prostitutes and clients are not.