Ghoster likes photo of me and my new gf

I was going out with a girl a while back. She seemed cool, and we had similar interests. She ended up ghosting me because I could preform in bed (couldn’t get up) when we decided to get physical.

She stated she was going through a lot mentally before ghosting, and I told her that I would give her some space. I still checked in occasionally to make sure she was mentally alright.

After getting bruised emotionally. I took some time for myself and eventually found a lovely woman. I recently posted picture of us out for Halloween. Weirdly enough, my ghoster liked my photo. She never interacted with my content prior to this, which made it really weird. Why would someone do this? Does this make them feel better for what they did?