Feeling lost

The last few months haven't been ideal, my babies father and I aren't together but he still comes around which makes it difficult for me. I love him and he says he loves me but we just aren't together. I just keep to myself and not say anything but I think that's why I feel the way I do.. I was thinking about writing him a letter to let everything out since it's probably be easier to get everything out rather then talk about it cuz I suck at explaining myself.. Is it a good idea?