You will have to learn to weather these emotions and care for yourself. Maybe with the help of a counselor, if that is an option. You need to assess the best way for you to handle your anxiety and loneliness, as if there is no gf and there never will be another gf. The next step is assessing whether you can work through this process and still save a piece of your attention and presence to offer a relationship. 

I went through a similar thing after a divorce. The marriage had no affection or emotional support. When I began talking to someone new I showed up with a craving for affection that was 16 years old. My alone time was full of loneliness and grief, and it felt like ages between every date. Lots of tears. On the other hand, I did a lot of great work on myself during that alone time. I thought about who I want to be and figured out how much of myself I could devote to a new relationship. I have a child from the marriage. I decided I only wanted to open up a couple days a week to a new relationship, and that made me feel very depressed about how anyone worth having would want more time and attention than that. But so far it has worked out quite nicely. My heart is full of love, even if my days are divided between different focuses. If you know what you are looking for, it is easier to find it. (If you obsess over what you do not want, then that is what you will keep seeing everywhere)

Be honest and vulnerable with your girlfriend about your anxieties. You are dating, and yet going through this alone. Not much will change if you are honest, and she dumps you. Alone now. Alone then. And there is always a possibility that honesty and communication will bring you closer together. Maybe she is interested in growing her capacity for affection. Maybe she would feel comfortable to experiment with that if you assure her that it’s not something you MUST HAVE from another person to fix all your problems.

There is no pain-free option for you. The good news is that almost every path (except lies or avoidance) will lead you through a difficult situation that will help you become a stronger person with more peace, love and patience to offer the world. Good luck!