I agree with JohnP and that maybe you should wait for the low carb until after your ulcer... afterall, low fat is another healthy way of eating. That being said, after years and years of concentrating/growing up thinking fattening things are horrible, I have a hard time eating low carb/high fat. I find it quite easy to eat low carb and low fat at the same time. Lots of salads - packed with lean mean (chicken), veggies, and low fat dressing. I also have Flat Out wraps - they are low carb and only 100 calories a piece, so with some chicken or turkey lunch meat toasted in the toaster oven can be SO DELICIOUS.
And don't underestimate the power of cauliflower. I turn it into pizza, mashed 'potatoes', stir fry with some lean beef, etc.
Good luck, whatever you do!