First of all, pretty much everyone talks differently through text than they do in person; it's not just you. You may not notice this in yourself and most other people, but we tend to be more honest and straightforward in written conversations. And in spoken conversation, we can joke, flirt, and be sarcastic a lot easier than we can be through text. So of course we are going to seem different in text and spoken conversations!
Second of all, if that's the reason why he broke up with you, then you shouldn't waste your time with someone like him. Breaking up with you for that reason is really stupid and pathetic, since his reason pretty much applies to everyone. I know that you still have feelings for him, but do you really want to be with someone who is easily put off by little things? Because to me, your ex seems like he is a bit paranoid and/or focuses on small things that don't really matter in a relationship in the long run. And since he's like that, who knows what else he might do in the future. He could get put off by another little thing and that's just frustrating. It's not healthy to be around people who only drive you up the wall.