Have you ever felt that having had to deal with your own mental health issues has given you the ability to mentor another? I don't think we have to have the solutions and be perfect ourselves to be able to be helpful to another. Sometimes just being able to relate gives us the ability to assist when it is needed. For example, do you not recognise and identify with another person going through a similar situation?
PsychCentral is an example of this happening all the time. Everyday people reach out - including yourself - to the others and much of what is said is valuable; even when we have not been able to help ourselves.