I had a similar experience recently. I reconnected with an ex (with whom I had had a challenging relationship, and who it had been difficult to break up with because I had strong feelings). It started out very connective, loving, and - most of all - familiar. Just last week, he pulled away and announced that he wasn't sure he wanted a serious relationship at all.
I agree with BeccyBean's comment, that at least I know for sure that this isn't for me. I had left last time because of the same push-pull behaviors. I had hoped that he had grown "ready" in the intervening time. He hadn't. I do still love him, but I have different aspirations for relationship - I want something in which I feel safe and chosen. I've had my share of "romantic friendships" without any commitment or intimacy, and that isn't what I want anymore.
At first I also felt "tricked." But after considering it over this last weekend, I believe that his feelings are genuine, but that he has barriers to intimacy that I may never understand. This is the challenge for me - to accept that I might not be able to understand his beliefs, behaviors, or priorities, and to be ok with this.
I'm exploring my own possibilities and creating my life. Revisiting an old relationship, just to be sure, isn't something I want to feel guilt or shame or pain about. People do it all the time; sometimes it is a magical reconnection, but more often (probably) one finds that many of the same dynamics are in place, and even though you can feel much change within, it takes two to rewrite a love story.
Consider it extra practice in letting go of outcomes. Being optimistic and hopeful is not a bad thing. You can name what you're feeling "disappointment" rather than "being taken advantage of."
It sounds like you're actively building a positive and connected life for yourself. Just consider this a blip of "revisiting to be sure" and keep on with all the activities that make you feel good about yourself.