I'm afraid of being alone.
There are worse things than being alone. I can tell you what they are.
When my AXGF ended things, I took that as an opportunity to reinvest in myself. Got my career back on track after it taking a hit after dealing with my AXGF's shenanigans, finished graduate school, and (when the timing was right) opened my heart to a woman who I'll likely be married to by this time next year.
But it was important for me to be alone for a while, and in this case "a while" meant nearly 4 years. I got honest with myself regarding my choices, and I learned how to be comfortable in my own skin I didn't need to date to feel complete.
What's worse than being alone? Being with someone who slowly kills your soul...