What in the world is he doing?

So me and my ex broke up like 6 months ago and he immediately got a new girlfriend (I know he cheated). So after he got the girlfriend we never had a proper conversation with each others. Sometimes he sents me some random texts on Snapchat (he never saves them they disappear) (like hello what’s up you look like this character etc). A few weeks ago he sent me a message saying that he misses me (to which I replied what the fck) but after that he acts like I don’t even exist. So I have two questions. Why he texts and never replies back? What did that I miss you mean?
What in the world is he doing?
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