Hi reachingoutuk,

I'm sorry to hear that. You were together for a decade and it felt like an emotional rollecoaster and you have been split for a year? I completely understand how painful that feels when our significant others have an emotional and / or physical affair.
Was your relationship witgh you uBPD ex tumultous for all of 10 years? Were things great in the beginning and maybe you saw irritional and unstable behavior peek through the cracks?
A criterion for BPD is a history of unstable and chaotic interpersonal relationships and a history of broken relationships. Often there is concurring alcohol and substance abuse with BPD and most often the substance abuse is treated before tackling BPD. Is she getting help for herself for her mental health?