The longest ride I have done is 120mi, so I may not be the best person to be answering this question. However, my training has been good this season, and I am sure that if I wanted to, I could be ready for 160 in a few weeks. Basically, you really do need to ramp up your mileage. I personally enjoy riding alone, so 75mi by myself on the open road on a sat morning, is thoroughly enjoyable. However, if you don't like that, find a couple of riding partners. I have done some rides where I ride the first 30mi myself, meet a friend along the way for 30mi, and ride the last 15-20 home on my own. This works well if your friends are not training for the same distances as you, but still want to get a shorter ride in. It is also good if your friends aren't quite as fit as you, because you'll be pacing yourself on an 80mi ride thereby helping you and your friends be more evening matched in terms of speed.

Food: As you ramp up your mileage, you will begin to figure out what works with you in terms of food. Eat before you get hungry. I always bring bananas with me on a long ride, in addition to cliff shot bloks and payday candybars. Somtimes a take trailmix, but that is usually when I am all out of payday candybars. Fruit leather works well for me too. Make sure to hydrate well during the ride. I usually carry a bottle of water and some kind of diluted sports drink. I start with the water, and by the end of the ride alternate between water and sports drink.

The most important thing is to have fun! Training is hard, but should be enjoyably so! Any chance that your co-worker will train with you?