While wanting to be partnered is natural and understandable, thinking that being partnered is going to magically fix everything isn't realistic. I KNOW it's tough. I had that "why not me" and "what's wrong with me" thinking going on and then when someone did pay attention to me, it didn't even matter what I thought, someone was interested and now I was whole. That strategy got me two divorces and currently separated from a RABF.
I'm now knocking on the door of old age and I finally get it. I finally have created a life that is full enough. I am enough. Me. I've created a life that is peaceful and fulfilling. It's got some joy, hope and serenity. I've worked on self-validating and not to compare myself to others AT ALL. They are not me and I am the best me that there is.
No one at that reunion, on FB, where ever is a better mother to your kids than you are. Take pride in that. When those "tapes" start playing in your head, put in a different tape. Write down your good qualities and your gratitudes and when you start to dwell in what you think you lack, remind yourself of all the good you are and you have.
Hugs - we've all been there.
When you create a life for yourself, no one can pull it away from you. Create love, peace, joy and serenity and more will flow to you.