I know that she has dealt with an eating disorder, another control issue, which she did not get help for.
Dating a man with obsessive compulsive personality disorder
These people take a lot of patience and biting of the tongue in order to communicate disagreement with their ideas, and sometimes this is simply not acceptable to most people; this has no easy answers and it is time for both people to visit a therapist, for help--with the non-ocpd personality voicing their perception strongly and decisively in the sessions.
Dating someone with obsessive compulsive personality disorder
There's one thing a person with ocd hates, it's when someone suggests they can be happy, be healthy, if we just "try" to do the things that scare us or even go cold turkey on doing the things that our disorders tell us to do.
This in mind, i feel that i can impart some advice to anyone who has started dating someone with ocd.
If you do not have the disorder yourself, then you need to understand that we are not your burden; we are people.
They tend to feel that they recognize the "right" way of doing things and translate this into control by believing that if no one else behaves correctly, then the ocpd person must take control or suffer the consequences--and if they doesn't take control, then the blame for inaction will fall on the ocpd's shoulders, and the blame is exaggerated because the ocpd personality punishes themself more severely than the matter naturally warrants.
About the disorder is the first step to understanding what kind of partner you need to be for your loved one.