2015 Chevy/GMC 2500 Diesel or Gas?

Ok, maybe this will help with the decision. I live 1.2 miles from my office, and 2.5 miles from my local courthouse (I'm an attorney). Most days now I drive about 5 miles or so total. Once every week or two I travel to a different city to go to court, but that is typically only 1/2hour or 1 hour away. I will be getting the 3/4 ton to pull our 3150 travel trailer (35 total feet) at approximately 7500lbs dry. We will probably pull the camper 1-2 times per month at most. We live 1.5hrs from the beach which is where we will normally be taking it in the summer.

Now, knowing my normal driving habits and use for the truck, does that change anything as far as gas vs. diesel? I am also looking at the F250's as well.