My first (ever and polyamorous) love recently ended our relationship in a fairly cruel and selfish way so I am right there with how first loves can be really intense. I'm still dealing with the aftermath. I agree with what's been said already. Sounds like maybe you expected poly fidelity while Drew was open to more relationships. And if that were true, it wouldn't invalidate your feelings of betrayal but perhaps he was not clear on your expectations. O, my ex, was almost 15 years older than me. Age doesn't have to mean anything but it can. Looking back on our relationship, I feel like he took advantage of my youthful naivety. Just be careful as sometimes age can come in and make things difficult. I guess I'm a bit biased right now but I think being someone's first is a big responsibility. Esp. if it's an adult relationship. If you have your first relationship in middle school, no one expects it to last and it hurts at the end but I think that having your first relationship as an adult can be a unique challenge.