My dp came from from his work Christmas do late Friday night. He fell asleep downstairs when I went down in the morning his morning alarm was going off so I went to turn it off and a messaged was shown from a girl he worked with. I looked through the message chain and some was normal conversation texting about the Christmas do they both went in but there was some flirty messages. Him telling her she will look fire in her outfit him telling her he can’t wait to see her. I am so beyond shocked by it all and I don’t really know what to do. We’ve been together 10 years and have 2 young dcs.