You are not alone, I graduated college last year and was a girl distance runner. I went through the same thing. I thought, well as long as I'm fueling my runs I'm fine, but would starved myself every other part of the day. I never took recovery into account and tried to eat as little as possible. I didn't think it could effect my running if I ate something before I ran, but I was so wrong. I started getting slower and slower, and it was terrible; my collegiate career was ruined because of it. Congrats on recognizing the need to change, it will be hard at first, but it will become easier. I remember the day I started to change, after I ate my normal small dinner, I said you know what I'm still hungry and ate until I was full. Then I realized what a relief it was to know that I could eat when I felt like it. After restricting for so long and finding ways to cope with the hunger and going to sleep thinking about food, and never feeling satisfied (its a miserable lifestyle), now I was free. Keep reminding yourself that you are allowed to eat, and your body is telling you to eat for a reason (it needs energy!).
-At first, you will gain weight and then over time, it will level out.
-Also, don't worry about gaining weight and it affecting your running. I gained weight, but with the added fuel, I was recovering so much better and feeling so much better! I was so surprised with the year I took off from running how fast I got into shape and how fast my times were.
-If your body is worrying about how to feed all the cells in your body, it most certainly won't be worrying about making you fast.
-The mindset takes time, but you will get there, I dealt with it for years, but now I am free, I know you can do it too! Realize that this is life and when you're staring yourself, that's not living life, and that's not what your body needs.
-Get into the habit of eating until you are full, eat meals/ snacks when you are hungry (the time on the clock doesn't matter, the clock has nothing to do with your body), eat a lot of healthy things and some unhealthy things (understand what a HAPPY balanced diet is and that eating a piece of cake and a cookie won't make you gain any weight).
-You can do this!!