My personal very nonmedical advice on dealing with this real fear.

I don’t remember exactly when I first heard of someone being afraid of success, but I remember scoffing at the idea. How could someone feel anything but happiness about their successes? Growing up in a family in which silent misery was the thing, and because I hated that fatalism, the idea of resisting success seemed daft to me.
No longer. I am successful now, and now I know what people mean when they talk about having difficulties dealing with success.
Now, to be fair, I’m not a raging success. I’m not famous. I’m not a millionaire. I’m not beloved by millions. But I have, through hard work, persistence, and the immense help of my wife, reached a really good place in life. I have the life I had dreamed of for so long. I have a job I love that pays the bills but leaves me enough time to pursue research and writing. I work remotely (even before the pandemic), which means I can live anywhere I want. So I do, in my favorite city in the world, Prague. I am very happily married with my soulmate, have a solid career, love where I live, have several years of savings in the bank — and yet, I feel anxious far too often.
What Is Fear of Success?
To understand what fear of success is, avoid pop psychology gibberish and look at more academic sources. Here’s a good medical explanation, Explaining the Fear of Success, or for deeper study, the book Fear of Success.
In a nutshell, the fear of success is when you are approaching or having success but are afflicted with guilt, anxiety, and feeling overwhelmed. Often, it afflicts people when they have reached goals that they struggled so long to reach. Your emotions become confusing. You anticipated feeling nothing but joy but now you have these jumble of fears and insecurities.
Some people feel they don’t deserve their success or that others will think they don’t deserve it, known as “imposter syndrome.” Others feel fear of losing the success they’ve attained. Some people fear being the target of unwanted attention, such as resentment, envy, or increased pressure to fulfill expectations. There isn’t a particular set of symptoms or a psychological diagnosis of fear of success, but it is something many people have to deal with. When people don’t address their fears of success, they fall into self-sabotaging behaviors that will ruin their accomplishments and happiness.
Dealing with the Fear of Success
The most important thing is to understand that your feelings of guilt and anxiety about being successful don’t mean that you are a fraud, undeserving, or crazy. I’m not a doctor, except in philosophy, and that doesn’t qualify me to give medical advice. I can, however, share my experience.
The anxiety that I came to realize was a fear of success started after my father died and while I was writing my latest book. In addition to the overall positivity in my life, the lifting of the burden of managing care for my father combined with the coming to fruition of my book pushed me into feeling overwhelmed. This was a new stage of life for me, a new level of freedom and accomplishment. How did I get here? Do I deserve this? What right do I have to enjoy this? Mostly, it was inchoate anxiety, as though things weren’t OK and I wasn’t OK.
For good and ill, I am a deeply thoughtful person (comes with being a philosopher), and the more I reflected on my anxiety, the more I realized it was because my new stage of life was foreign to me. I did not know how to be a success because I had never believed I was (and probably hadn’t been). I was used to struggle and disappointment.
This is what the fear of success is for me and probably for many other people. We got so used to struggling that not struggling feels strange and wrong. We feel unsure of ourselves and how to be, and we feel anxious and overwhelmed. Deep down we don’t want to be struggling or failing, but it is familiar, so it is perversely comfortable to stay there. Success, despite how much we genuinely want it, disrupts our familiar patterns.
Getting used to new patterns and ways of living takes time. It’s a process without shortcuts or quick fixes. My personal very nonmedical advice is, more than anything, to give yourself a break. Change is difficult, and success means your life is changing.
Of course, it’s going to be stressful and a little strange to accept new circumstances. When you feel overwhelmed or anxious, stop, take a breath, and ask yourself what’s really going on in your life and within you. It’s not always easy to accept that everything’s okay. And that’s okay. Any negative feelings you have may be connected with your past. Explore those feelings and have a conversation with them. For me, it helps to be able to say to myself that my anxiety is something I learned in the past but that I don’t have to live in the past anymore. I don’t need to fear the future or success. You don’t either.