I'll try to make this brief. I am new to this so please bare with me. So, I have an awkward situation I would like a little feedback on. I have a very good friend that I would like to be in my WP. She is actually my cousin's ex-wife. We became fast friends while they were dating. The divorce was pretty ugly, but it was about 8 years ago. I stayed neutral throughout the divorce, I could see they were just not right for each other. My cousin has been happily remarried for a few years. I feel I should mention my friend was an integral part to me meeting my DF. She also helped him pick out the E-ring and has been helping me with planning. She has already said she understands the family drama and is okay not being a BM. I just don't want anyone to be uncomfortable and cause an awkward situation. Would it be a good idea to give him a heads up maybe? I am at a loss. I do not want to exclude a very dear friend, but I also do not want to upset my family either. 
TIA