Am I still in love with my ex or am I just obsessed and cannot accept the rejection?
Break-ups can be so difficult, especially when we do not receive the closure or understanding that we are looking for. It seems from your comments that you were very close with your ex and did not want the relationship to end. It also sounds like there was some uncertainty and communication barriers that were not addressed within your relationship together. I am curious if you are yearning for the connection that you had with her, or if it is more how you felt when you were in a relationship and being in a relationship with someone.
When there is vulnerability and trust given in a relationship and it is not always reciprocated or situations arise where trust is broken or questioned, it makes for hardships in communication, and trust. Barriers then begin to be built up and then in turn creates more strain between you both. By you reflecting now on your thought process and actions, it shows that you are wanting to understand the relationship, the break-up, and where this leaves you now. Moving on is difficult to say the least, but allowing yourself some self-reflection time and room to process and grieve is very important.
Impulsivity to know more information or wanting to "connect the dots" can spawn from past hurts or unresolved issues. Sometimes we do not always receive the understanding and closure that we are hoping for. This is where the personal growth work can take place. Begin by looking into and understanding the questions that you have around why you may feel compelled to know more or find out exactly what she is doing and what has been going on. Internal Family Systems (IFS) is an evidence-based therapy model that focuses on the fact that we all have parts within ourselves that each play a specific role, and our core Self is where we are able to integrate and heal. By noticing, acknowledging and inviting certain parts within ourselves, it becomes less judgmental or self-criticizing and more about acceptance and understanding why certain parts have functioned the way that they have for so long. Moving then toward our core Self, which knows how to heal and remain in a healthy state is the ultimate goal. "You are the One You've Been Waiting For" by Richard Schwartz, the founder of IFS would be a great book to begin reading during this transition in your life.
I wish you luck and hope that you found some of this information helpful in your self-growth and therapy journey.