Welcome to HealthcareMagic forum,
First I would like to comment is I am not sure if there is any treatment like spray which is used for treating epilepsy
Epilepsy has been misunderstood by many individuals. After many studies it has been proved that people suffering with epilepsy can have normal life and family. All that needs is proper medical care.
If she is indeed suffering from it, she needs to be properly evaluated by a neurologist. With the help of appropriate antiepileptics (which is usually oral tablets) seizures can be prevented and your fiancée can be as normal as any other girl. Discuss with her about her treatment and encourage her to consult a neurologist
if she hasn't met any yet.
With proper medication and your care, she would be able to lead a normal life.
Hope my point is clear.
Wish you a happy married life