Dealing with Insecurity in a BPD Relationship

does anyone else with bpd have a very unhealthy insecurity with their S/O (FP)? me and my bfs relationship is very healthy as hes researched bpd and understands my thought process and I'm going through treatment, but I still find myself constantly switching between knowing he loves me and would never hurt me, to believing he will find someone else instantly. he got hired at a new job that will require traveling, and ive been a mess at the thought of him traveling with another women. I'm so happy he received the job as it's his dream, but my heart cant seem to stay away from the "what if's" that could but probably will never happen. I get insanely jealous when other women are mentioned, and although I never act on these thoughts, It still drives me insane that I have them. I know it's not right and ive tried clearing them out of my head, but I just cant seem to. anyone else deal with this? and how do you deal?