Should I see him?

Hi Brooke!
I broke up with a guy around 6 months ago for valid reasons but I still have very strong feelings for him and think of him often. We are in a little bit of contact but our main contact is a charity project we both were working on before the split.
I have not seen him for almost 4 months and although I miss him a lot, I feel not seeing him is helping me get over the situation. I had a very peaceful thought about a month ago when struggling during a bad week that, if I want, I never have to see him again. As I said, this felt very peaceful.
The client we are working on the project for, now wants us to have an in person meeting in the next 1-2 weeks. I am feeling nervous about it already, but also very excited to see him.
If I want, I can completely avoid the meeting, however I also thought it would be a good chance to observe my feelings and adjust to being around him with my new way of thinking. My biggest fear is sliding backwards after seeing him and regressing in getting over him.
I have tried a model below if I do see him and kept the second one quite neutral as I know I’m not over him yet.

C – I will see him
T – I’m so nervous, I miss him so much, I want him to want me
F – anxiety, rejection, longing
A – Be nervous around him, not be present, replay the situation over and over after I see him
R – Obsession, never getting over him

C – I will see him
T – I am here to work on the charity project, I want to be his friend
F – Calmness, stability
A – Work on the project in the moment, be nice to him, then leave
R – Experience completed, on to the next experience

What do you think? Should I go ahead with the meeting or avoid seeing him altogether?