Does the fact that your kids live full-time with their dad make you any less of a mother? No. Okay then. So why not celebrate? You are part of their whole. Without you, they wouldn’t exist. You are still their mom. No one took that honor away from you.
Our friends leave because they no longer know how to be our friend. The common bond had been disrupted. The cord had been broken. They don't know what to do or how to respond anymore. And neither do I.