I'm in a bit of a tricky situation. I'm working as a tour guide over the summer and am contracted to do three tours. It's a three week long tour and involves a lot of long (and uncomfortable) bus journeys, often without breaks. I thought it would be a great opportunity to travel (and it is) but it's far more strenuous than I thought. I've also just accepted a new job, one which will help me to progress within my chosen field (not tourism!) but I will have to miss the first two weeks due to the tour. I feel really bad but I just don't think I want to do the third tour, which is one month away. My contract states I need to give one month's notice but I'm really worried about quitting and how it will affect my relationship with the company while I'm touring. What should I do?