Crazy Ex Lying about CDV.

Hi, my name is David and me and my girlfriend have just broken up about two weeks ago. Since we have a lease in both of our names we tried to co-exist. It worked for a few days and then on the 9th I began asking her simple questions about why she broke up with me while I was all the way in California. We live in South Carolina by the way.
After that she became very defensive and we started arguing but it never went further than verbal until she punched me in the chest. I guess she was hoping I would hit her or something. Anyway, a man named Sgt. Cain called me today on the 11th and said he was investigating what happened on the 9th and wanted me to come down for a statement.
Apparently, my ex had told the deputies that I kicked, punched and grabbed her enough so that bruises formed. I never touched her, not once, and I'm sure people hear this all of the time but I swear on my life I didn't do anything to her.
Moving on, I believe that she has or is trying to file a CDV against me and possibly a restraining order. I asked the Sgt. what I would have to do to put a restraining order against her and he said, "Well, I wanna talk a little about that with you on Monday."

I feel that I am being investigated for a crime based on lies. My ex has a long and recent history of Schizophrenia, Manic Episodes, Depression, Suicide Attempts and Bi Polar Disorder. I have no criminal record and have never hit a women in my life. She is making a huge deal out of this.

Anyway, what do you guys think the Sheriff's Dept. is going to try and do? They want me to come to the station on Monday to give a statement. Should I do so? And if so, should I have an attorney present? I already have informed my attorney of the situation and he is on call.
I just need some advice, men always go down in CDV cases no matter what and I am so innocent it sickens me. Any advice would be helpful.

Thanks,

David