Should I write him a letter

So recently my SO and I broke up bc he hurt me really bad . We are having a kid together so I want no drama between us but I can't even have a convo with him with out bursting out in tears , should I write a letter to him to show my feelings . I feel like it's the only way for him to see how I felt about everything and understand . I don't know if that's immature but I am super emotional lately and I don't want to keep crying .