I'm in a relationship with someone with characteristics of both BPD and NDP and we've been together for almost 7 years.

It's not been easy at all. In fact, it's been my worst relationship so far because of how his deep seated insecurities has damaged my self-worth, security, and reputation.

My advice to you is to work on these behaviors with a professional and use this need to be in a healthy relationship to be your motivation.