Breakup and chronic fear of loneliness

I got broken up with a couple days ago.

I’m going through the ringer emotionally, but what I’m struggling with the most is the idea of being alone. I’ve always had a fear of being alone or feeling lonely. I feel like I live in a place of scarcity when it comes to this — this is a chronic problem that I have, and I’m not quite sure how to get out of this state of mind.

I had a somewhat isolated childhood and am an only child, but I’ve also never lived completely by myself before… I’ve always had parents or a roommate or a boyfriend. I just moved to a new city with my now-ex boyfriend not too long ago. Although I have some new friends here that I can hang out with, I still feel so alone and I’m so scared of the prospect of being in a house by myself.

I don’t want to act from this emotion moving forward… or do something rash out of fear, like jump into a new relationship before I’m ready, or get a dog purely out of sadness. I want to “be done” with this feeling so badly. I want to be comfortable and confident being by myself before I get into my next (and hopefully last) relationship). What can I do? How can I look at this differently?

Thank you!