It could mean she doesn't want to get hurt again...Just go out, have fun, let her lead the pace. Don't kiss her until you get strong signals from her that she wants you to.
And don't have sex with her for a while. Maybe it will take her 7 or 8 dates, whatever SHE WANTS. Be patient, but let her know you find her desirable by giving her compliments, checking her out a little, that kind of stuff...but not creepy, just a little bit...
Be confident, laid back, fun, easy. Her heart is still healing. You don't want her to rush into things with you, then six months later back herself off.
Oh, and if she wants to talk about her ex, don't let her go on too much. You could slip into friend zone. She has enough girlfriends to discuss him with. Be the new MAN, who is not associated with him in any way.
It might be good for you to find out why they broke up, but if she goes on and on about him, you could say, "Wow, I don't know how you put up with that." Then change the subject and make things fun....(my new boyfriend did that and it worked great!)
Enjoy yourself and relax. If she was in a relationship for 5 years, then she is definitely loyal, which is good for you...