I got the train into work today as I do a few times a week. It's a 45 minute train journey and I often use the time to catch up on work and prep for the day or I just enjoy some quiet time. This morning I was walking and passed by someone I know well on the platform. I carried on walking to the front of the train. We said hi to one another but my social battery is easily drained and I just don't feel like making small talk for 45 mins. Would you think this is rude?