Which relations can a schizophrenic person handle?

Dear Sir/Madam.
I hope that you can give me some pointers to deal with my particular relationship problem with a person who is coping with schizophrenia.My fiance Michelle and I are going out 8 years and are due to be married this year.She was diagnosed with this illness in her teens after a suicide attempt.She is on medication for her illness.She is very private about her illness and is allways reluctant to talk about it.I have respected her privacy and have never pushed her into talking about it if she felt uncomfortable about it.
On Jan 4th she told me that the engagement was off and that she did not want to get married to me.She contradicted herself in the reasons given.Only some days before she was discussing the wedding list and the various merits of different wedding venues.
I have noticed a subtle change in her personality in the week after Christmass.
Have you any suggestions as to whether this sudden decision is influenced by her illness.
I know from research that failure to maintain social relationships is a distinguishing feature of schizophrenia.
I dont know if she is continuing with her medication .
Hoping that you can give me some pointers to decide if she has made a rational decision or is exhibiting a type of schizophrenic relapse.
Looking forward to your experienced opinions
James John Porter.

It is often too hard for a schizofrenic person to live up to all expectations on a married person, even if she is taking medicine. Her choice is realistic if she feels that a marriage would be more than she can handle. Schizofrenia is a very serious illness.