Hi keysmiami,
Too many texts pouring my heart out trying to get an explanation to make any sense out of such a drastic change with only one sentence responses.
Indifference is tough. I'm sorry.
My ex still does this; ignores many messages, responds mostly if it's something for her needs and many times one word or three word answers. It's hurtful.
I think working out's a good idea. It'll boost your mood too.
It helps to talk.
Your friend has good advice and he means well. A break-up with someone with a personality disorder is tough and he may not understand how painful this is.