Why is my friend incapable of supporting me on social media?

I’m in this friendship group it’s me and this other girl. I have noticed that of the girls in the friendship group, Emily always likes and supports my other friends posts, but she never ever likes anything I post. I see that she is always active and online and she is always reacting to the other girls post with a love heart but she ignores mine. I know she sees mine too because she views all my stories I post. She also makes comments about what I post in person like “I keep seeing you going out on nights out and I don’t know how you manage to do that and function at work the next day. I couldn’t do that” except the other girl in the friendship group posts night out photos and she has no issue liking her photos and supporting her, and commenting nice things on her photos.

The other day I uploaded a photo of me on my birthday and she couldn’t bring herself to like my birthday post, even though when it was the other girls birthday she hearted her photo and commented “gorgeous girl”. Then she messaged me privately about the photo I uploaded saying “I saw your birthday post you look nice happy birthday” but she couldn’t even support me with it on social media.

Why can’t she ever bring herself to like my post but can like the other girls post easily?

Why is my friend incapable of supporting me on social media?
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