When you let go of something from an emotional perspective, you are ready to move on from it, too. Let's say that you are made redundant from your job and out of work for a period. If you remain upset about the loss of your job and the perceived injustice of your situation, then you are probably not going to be in a fit emotional state to seek other sources of employment and to nail any interviews you might get. In short, you won't be able to move on. However, if you can let go of the anxiety you may genuinely feel about losing your job and get into a psychologically fitter state as a result, then you are more likely to move on and find a new role that suits you. In other words, they are not the same thing, whether you are talking about jobs or other sorts of life losses. Without letting go, however, it is much harder to genuinely move on.