Kin and Coping. Its Simple.

If you are fictionkin and you are mentally ill, it is natural to fall back on your kin identity as a method of coping with your depression/anxiety/etc.

However

Being mentally ill and taking on the identity of a fictional character purely as a method of coping with your illness does not then make you fictionkin. 

Its a totally okay and fine and valid thing to do to help yourself. But it does not make you fictionkin. The word for that would be fiction-hearted.

Being fictionkin is something that you either are or you are not. It is not an identity that you can choose or deliberately cultivate for any reason. It is something that was always in you that you discover about yourself.

Being fictionkin is not a choice.

Mentally ill fictionkin can rely on their kin identities for support, but you can not ‘become’ fictionkin to cope with mental illness.