Although it is great to feel this pressure to perform, it's important that you are able to put in the work, in the face of obstacles, fatigue, boredom, stress and distractions to do other things, all the time. In other words, your motivation to train in January, February and March should be just as strong as your motivation to train in May, June and July.
Pulling out after only swimming and biking was hard. Very hard. I had never dealt with anything like that before.
Now, when I feel like not doing much, I look back at that time and use it as the extra power and motivation that I need to get myself to start and finish a workout. Because I CAN. I don't have an injury that prevents me from working out. I'm not in pain. I'm healthy.