Is your co-worker in therapy? BPD is not treated with medication but rather therapy. Medication can be for co-occurring disorders. DBT is one of the successful therapies used for BPD. As stated by suki, it takes years, and it takes a willingness on the bpd's part to participate in their own recovery and work it 24/7. And loved ones also need to be involved in the recovery process for it to be successful. BPD is a heart-breaking disorder, usually one that is borne from childhood traumas/abuses; I experienced it with my exgf. Here's the site I visit frequently as I continue to recover from the remaining emotional damage from that relationship:
http://www.bpdcentral.com/resources/...vabuse.shtmltp
((hugs)) and good luck to you.