Yes, if you are in separation, when you view the current 3D situation of your Twin Flame dynamic it looks like your twin has indeed rejected you. That they don't understand or care anymore about the connection, even if it had been blissful for both of you at one point.

But you have to understand that so many times, things are not what they seem to be. And this is so true about this TF dynamic, because it is very higher dimensional, so we cannot see its underpinnings well in our limited 3D viewpoint.

Before coming to Earth, you and your twin fully knew that when you'd be incarnated here, you would be taking in a whole lot of negative energy, since this Earth system is very negative. You knew you would be enduring different types of trauma, acquiring fears, taking in negative beliefs in the form of programing/conditioning. You knew you would be struggling with self-love and self-appreciation.

Since you knew that this would happen, you planned that once you'd meet each other again on Earth, you would be entering a process of eliminating this negativity that you had accumulated within. And the fastest and most helpful way to do this would be for your twin to say or do hurtful things to you that would trigger negative emotions in you. In this way you would become aware of your negativity and wounds and work to heal them. You would thus be elevating your energetical state.

This negativity that both twins have accumulated within actually works as a negative wall between them, and it's what causes separation. Your runner twin subconsciously sensed the negativity. So even though they spent blissful moments with you, and they know that they cannot have that sort of connection with anyone else, your twin still felt compelled to run. Because they felt overwhelmed, tired, put off by this negative barrier. And to protect themselves, the only solution they found was to get away from it. Which meant, to get away from you.

Therefore, your twin did not reject you. They did not reject the connection either. What they rejected, was the negativity within both of you.

Running away from the negativity is exactly what they had promised you before incarnating. Even if they knew that you would painfully believe that they were rejecting you. But it is all a mechanism, designed by both of you so you would start your process of healing and uplifting yourself.

As a twin flame coach and researcher, I hope this perspective will help you understand what happened with your twin, because of course in 3D it is very baffling and painful to see the person you love with all your being, walk away from you after all that you have shared with each other. And they might have given you some sort of excuse or justification for having run or treating you that way, one that their 3D mind came up with because they don't really know what subconsciously and energetically happened to them.

But now you have the explanation. Now you can begin understanding that from a higher perspective your twin loves you infinitely and unconditionally, but here in 3D they could not help but run from the negativity, and thus the connection. They did it so you start a very beneficial process for you. Because even if you've forgotten it, this is what you decided you would do once you'd meet your twin. And uplifting your energy is not only 100% beneficial for you, but is what gets you closer to Union too.