I started a new job 3 months ago. Today is one of the team's birthday. They are all going out this eve but I haven't been invited. It seems to be from a group chat that they had prior to me joining so not a deliberate exclusion. I am trying not to feel offended but they have been talking about it today, what they are wearing etc and no one has thought to either invite me, or at least say something about directly to me,or invite me to join the WhatsApp. Argh. Help me not to feel like a left out child!