What is going on with my husband?

We got married in August. It was an amazing ceremony. Both of us are and were extremely happy. But on his ex's birthday he visited her Instagram and liked a reel.(she's a nature photographer)

To be clear she wasn't a girlfriend ever. just a girl he crushed on since high school. he was in love with her for over a decade. They were in contact all this time but never got together. He was quite hung up on her as I've heard from other people. But she got married last year. I kinda think that it was right after she got married that he made our relationship public. I don't know maybe I'm overthinking.

After September there was no instance like that. I'm sure. But could that be worrisome? Maybe just nostalgia? It'll get better Right?

What is going on with my husband?
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