Experiencing a Breakup

Hello everyone. I recently was just broken up with after a 2 year relationship. I feel like a failure, I keep reflecting on what I could've done different, better etc. The worst part is that fear and anxiety held me back from doing the very thing I knew I should've been doing in the relationship and for that lack of progress to be the reason for the break up is the hardest thing to deal with right now. The relationship wasn't perfect by any means but she was my first real serious relationship and first true love.

Some background: We started dating our junior year of college and then she graduated early. So that alone was a hard time as she moved back home and I was left to finish school "without her". But I made it through and after I graduated we actually got jobs at the same company in the same city at the same time and ended up getting apartments in the same building (different apartments though). In my mind the stars aligned and God was setting me up to be with the women He had meant for me to be with. But as time went on I got complacent and took for granted the stars aligning. I didn't see the need to make friends outside our relationship as it brought me great anxiety and with my job I am expected to move on a moments notice. So building meaningful relationships didn't seem to make sense if I would just be leaving them behind after a year or so. She eventually made the jump to create those friendships and face that looming fear we both shared, but she did it alone. This is key because I didn't know she felt alone in this but that is ultimately why things ended. I knew I should've been growing but let fear control my life instead. Now I have lost the one thing that meant the most to me and I am all alone in a big city feeling like I don't belong.

I am sorry for the word vomit but I just really need help, advice, just someone to listen. There's times were I get stuck in an endless loop of regret and "what-ifs". Thank you for reading.