How to start over again?

The first step that I would suggest is trying to remember how your work ethic is and the positive aspects of why you were looking forward to going to work before. Sometimes when you can remember how things were when you first started, it could be very motivating for your next steps. In addition to this, it is going to recognize your strengths and ways that you would be able to get validation within your work environment and have motivation to be consistent within your responsibilities. Additionally, when you experienced sadness/anxiety before, what were the ways that were helpful for you at the time that got you through to carrying on your routine as always, despite the level of emotions you were going through.

Additionally, it is good to have an understanding of everything that is going on in your life that might be influencing the increase of emotions and difficulty with getting back into your routine. What are the triggers of your fears? Are there situations with people, new challenges, our overall confidence issues within your work environment? Or has there been an increase of stress overall surrounding you with another aspect of your life? Having an understanding of the sources of these fears will definitely help you start to make connections in order to know how to search overcome them.

In regards to how to best address these fears as they arise, You can try to imagine issues such as asking yourself what is the worst that could happen? If you were to go back to work. I know that you said that you were mentally drained, is it more of an issue of feeling like you don't have any energy left in order to encounter new situations or that others won't understand that you will need assistance as situations arise.

Additionally, it depends on the work environment as well. If you are in a environment in which you are often interrupted or that you feel like you were not able to get on top of tasks being completed due to there being an excessive amount, then it is understandable that you could feel maybe that you cannot keep up due to the high demands. And some work environments, even if you were talented, there is only so much that one person can do on their own. Are there other aspects of the job that are also creating the stress? Such as others not respecting your boundaries or not understanding or respecting your feedback.

I encourage you to assess your work environment and see if it is time to be in a different role, continue to focus on the challenges of the current role, or look for another environment entirely. However, it could be about addressing the circumstances around you, reminding yourself of your own job responsibilities, and asking for support from others in your work environment as needed. The best that you can do at this time is to reassess your overall view of your talents, your work experiences, and ways that you can further see yourself in the capacity of a job overall. Just know that it is important to give an opportunity a try, even if you're not completely sure, if you were having difficulty with going back overall, it is good to start working in a position or situation that could at least just get you back out into getting accustomed to a work environment again and dealing with other people. Also this will help you be reminded of your work ethic and strengths that you bring. 

Good luck in your upcoming steps.