Were you thinking it was the marriage thing? I know some people my age who have recently gotten married and it's crazy to me to do that to yourself. You did answer my question, and it was very reassuring to read your comment and realize that A: this is normal, B: I'm not crazy, and C: maybe this isn't a bad thing. There are some things I'm committed to as ideas, interests, and friends. But beyond that it's a total crap-shoot right now.
When I was writing about relationships, it was more about friends and acquaintances and casual relationships. I've come across in my life absolutely amazing people who are so giving and compassionate, they were the deciding factor that made me realize I wanted to be like them, and needed to change, learn how to commit, to make that happen. I'm at least a decade older than you, however, so that may or not be relevant for you. Something else, may or may not be relevant, I'm throwing this out there, in the off chance it might be. Another game changer for me was writing out long-term plans. Meaning, 2, 5, 10, 15, 20 years from now. Where I want to be when I'm 50-60. Where I want to be when I'm 40, and so on. Mapping out the steps I'd need to take... Not sure if I'm making sense. Basic idea: instead of using just one life plan (marriage, kids, job, retirement) and focusing all your frustrations, expectations onto that, try breaking it down into smaller sections. What would make you happy to accomplish in the next 5 years. What would you have to do in the next two years to make your 5 year goal possible. And so forth. This introduces flexibility, adaptability, you can look at it in a modular fashion, instead of an iron/concrete/heavy goal on your shoulders causing you anxiety, dragging you down crushing your hopes. Like, when you get to the end of the 2 year plan, you may realize your 5 year plan may've changed somewhat. Adapt, change perspective (this is a basic fact about getting older, perspective is in a permanent state of flux), but keep moving forward, keep setting goals. Oh, just realized I may've misunderstood the first question in your comment. If so, I initially thought before reading your post it was about being committed in a 5150 sense.