If you say goodbye in person, they're not going to understand. It will blow up in your face. I'd recommend using the site search but I can't even think of any search terms right now. There are sooooo many examples of how people regret trying to say goodbye, prepare others, explain their perspective or stance, etc. Others who aren't consciously pro-choice tend to freak out, try to get you to get help, call emergency services, stop being your friend or do the opposite and start hovering, be pro-lifey, and just basically not understand. Then afterward you'll be posting a new thread about what a shit show it was, how much you regret saying anything, etc.
Spoken by a former pro-lifey person who became pro-choicey, eventually joined this site and, after 2 1/2 very active months, has seen pretty much every subject cycle through multiple times. This is a common subject with consistent regrets and woes.
TL;DR
Save it for the goodbye letters. If you need to vent and get support, post here. If you need to cry about how you want to say goodbye in person, post here.