No you didn't assault her in any way unless you physically made her feel pain. On the other hand if you keep following her like that she could say you are a stalker. If everything you said is true i feel bad for you, she cheats on you and acts like a real you know to you while you wanna save the relationship. she even said then die, that's a big low. Sounds like she is no good for you man, let her go probably doesn't deserve you.