Welcome tyrex13
It is good that you sound like you are working together on this.
It is important to realize that BPD can have quite a traumatic effect on many partners and this support group is mainly aimed at that group. If you are sharing this membership with your partner they could find it very triggering and distressing as some of the discussions can be blunt and raw.
Some resources which may be useful for you partner can be found in the link below
Resources for BPD SufferersUltimately any diagnosis would need to be made by a professional in the field. Many folks do make big inroads without the need for a diagnosis.
Generally for partners of people with BPD the focus needs to shift from trying to "fix" them to learning how we can better communicate and interact with them. ie how to stop making things worse than they need be. This is the first step to reducing the inevitable conflict that keeps the cycle turning
Waverider