Hi @naebell
A very warm welcome to Sane. Sorry to read of the struggle you and your fiancé are dealing with. It is very hard to watch as a carer as that feeling of helplessness wells up. I went through this myself whilst caring for my daughter whom was diagnosed with bi-polar and BPD at that time. It's hard and heart wrenching to witness them self destructing being not sure what to do. Sending you a warm hug 🤗
Is your fiancé currently under the support of a medical professional for treatment/counselling? If you are at all concerned please do not hesitate to ring the mental health crisis team or local hospital in your area.
If you need additional help and guidance there is Carers Australia and Mental Health Carers Australia which you can google for contact details and links.
Please feel free to talk here as much as you need as others whom also care for partners/loved ones with MI with join in soon.