I just need to put this down in writing, who knows it might even help. 
My job is great and I usually get at least one trip a year abroad with work and it’s more like a vacation than work.  When I’m there in the hotel at the pool, I couldn’t be happier and never regret going. That being said, the weeks that lead up to the trip absolutely cripple me physically. I write out long emails to my boss with completely fabricated scenarios to get me out of the trip (he knows I have anxiety) I also really hate flying but refuse to ever take Valium again as it’s seriously bad news. I’m worried my colleagues will see me clenching my jaw, gagging and running off to be sick. How do I build myself up to go?