feeling alone

I've just been feeling so alone lately. I thought getting myself on a regular routine would help but so far it hasn't. I thought keeping myself busy at work and at home would distract my mind enough from thinking about what's missing in my life. All I can keep thinking about is I don't have anyone special in my life that I love and loves me in return. Or that I don't have any children. And with my birthday coming up, it just makes everything feel worse. I keep telling my family I don't want to celebrate my birthday but they don't listen. So I feel like I'm force to celebrate a day I much rather forget. I'm almost 39 btw. The other problem is I still love my ex. But he's with someone else. He keeps messaging me but I don't reply back. I did the last time because I thought I could get him to understand how much he hurt me. He kept making me feel so wanted even when weren't together anymore. Even on the day he told meet someone else, he told me he wanted me and needed me. I tried moving on and meeting other guys. I even was seeing someone else briefly, but I still couldn't stop thinking about my ex. I just don't know what to do. And to anyone who says I'll meet someone eventually, I know your intentions are good, but it actually makes me feel worse. It's because I don't feel like it's true.