Yeah he did sound like an incel

I'm not fan of the dialogue, but like i said, disliking the thought of the person you love being with someone else is not being an incel.

He treated her wrongly, verbally abused her and made her kill him

Eren definitely went overboard, i'm not arguing whether their relationship was a toxic one, because i do think it was, but none of that indicates Eren being an incel, him going overboard in order to make Miakasa hate him and give up on him is the exact opposite of what an incel would do.

now it seems like he wants her to live with that trauma.

I really didn't get that vibe at all, it seemed like Eren wanted Mikasa to move on from him, like his last words to her in that dream sequence.

And not to mention now that it's canon that everything he did so far is because he got "familyzoned" by her

I don't really understand how you came to that conclusion, seems like Eren did all this because it was destiny or something, i'm not a huge fan of that explanation.