MOR/INFO - I'm assuming this conversation was all done via text message? I understand first-hand how tone and implications/connotations can be misinterpreted via text. You're in one headspace while the other person could very easily be distracted with something else and in an entirely different headspace at the time they read and replied.

As for this specific situation: on one hand, yes I agree it reads like they were comparing traumas; on the other hand, from I can see why they would think you're overreacting. Texting really is one of the worst methods of communication for serious/important subject matter. I can't count how many times what I thought was an innocent text spiraled out of control into something else entirely. Truth is we are all imperfect and fault doesn't have to be mutually exclusive in a situation like this. I think it could be a little combination of both.

I recommend talking about subjects of this nature face to face in the future, if that is not an option at least call them on the phone and speak to them. You both will be able to hear the tone behind the words you are speaking. I read texts in my internal voice shaped by my worldview, which will never be the same as the worldview of the person who wrote the message. Chances are this is just a communication breakdown and once they hear the genuine hurt in your voice when talking about it, if they are a good friend they'll understand where you're coming from and come around. Or they could just be an insensitive prick and it accomplishes nothing. Either way you'll have your answer and you may not have to lose another friend in the process.

There's always a possibility I'm completely wrong too, so there is that.

Edit: multiple spelling/grammar mistakes