Why did he go crazy after we had sex?

Second time I slept with my boyfriend. We had gotten really close emotionally recently. Talked out my fears and he reassured me.

Anyway, had a date. He was really anxious and irritable when out. I think he has problems with open spaces. At the time, I was pissed but now I see he was going out of his comfort zone.

We had a nice amazing session. Lots of kissing, eye contact 2 rounds cuddling the whole everything.

Next day basically unreachable but sent a sweet morning text the day after.

Contact nose dived and he answered to say nothing is wrong he is working and stopped calling texting.

Then he sent a message saying his cousin died. Then silence.

Then he messaged me a photo of him at a park near my house and him sitting alone on the bench. I asked if he was hinting at me coming to join him then he said he was late. I said we had no plans. The he said his mind is messed up and he doesn't know what is wrong.

Then yesterday, I get a message from this random number that was trying to hook up with me.

The person couldn't (or wouldn't) say how they got my number.

In my gut I knew he had something to do with it.

I screenshotted it and asked him why he was doing this and he said he was doing nothing. Now silence again.

On his socials, he is posting marriage proposal and wedding vids and music the timestamp matches the same time this rando number was texting me.

He has two numbers and blocked me on one. This is something he does when he gets mental. He will ice out everyone but post on social. In the past, he would ice me out totally but this time he kept sporadic contact because we dicussed it.

I checked the profile pic from another number and it's a picture of a room and not anything flirty.

If it's ghosting, it's a strange way to ghost someone so, I don't know what to make of it. He's shown me when he's chill that he is super into me and will support me and be there for me. It's like a switch flipped.

Thoughts?

Why did he go crazy after we had sex?
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2 mo
Spoke with him. It's obvious he's going through some sort a manic state and is isolating. He still answers phone calls and try to keep in touch but he's a bit off the wall.
Why did he go crazy after we had sex?
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