I have been through something similar...very similar. It was even in the beginning, but after a while...you just sense or feel something is different. He always acted the same. Friendly, charming, attentive, when I messaged first. But then...I was always the only one initiating. It made me anxious and depressed too. I remember crying sometimes at night and I couldn't understand why because he was so nice and not being specifically mean. But I also sensed he was holding things back and something wasn't right. I'd send a selfie and he would be nice but disinterested. Yet say in another conversation he really likes me. Mixed signals are very confusing.

I went through something traumatic and sought support from him and he brushed me off. That is about the time I chose to walk away. Someone who is really into you, they will really show up.

Whenever someone's behavior changes, that is either a yellow flag or red flag for me. You are valid for feeling upset about this. The advice already given is good advice. I have nothing more to add except to say I know exactly how you feel and you are not crazy, too sensitive or overreacting.