Self-Directed Positive Psychology Intervention for Newly Diagnosed Multiple Sclerosis

The goal of this clinical trial is to learn whether positive psychology (PP) exercises such as writing a letter of gratitude or remembering a past success can help individuals with newly diagnosed multiple sclerosis (MS) to feel more hopeful, happy, and healthy. The main questions it aims to answer are: * Is a five-week self-directed PP training intervention feasible and acceptable to individuals with newly diagnosed MS? * Does the completion of a five-week self-directed PP training intervention improve positive affect, emotional function and health-related quality of life (HRQOL) in individuals with newly diagnosed MS? * Are improvements in positive affect, emotional function and HRQOL maintained after the completion of the intervention? Participants will be randomized to the intervention or waitlist control group. There will be an intervention phase (weeks 1-5) and an extension phase (weeks 6-10). All participants will complete questionnaires at enrollment, 5 weeks and 10 weeks. They will complete 5 weeks of self-directed PP training exercises, either during the intervention phase (intervention group) or extension phase (waitlist control group) of the study. Researchers will compare participants in the intervention and waitlist control groups at the end of the intervention phase to see if there are improvements in positive affect, emotional function and HRQOL. For subjects in the intervention group who demonstrate improvement, researchers will determine if the benefit is maintained by comparing positive affect, emotional function and HRQOL at the completion of the intervention and extension phases of the study.