If she makes you happy and you want to ask her on a date, ask her! Don’t let your friend scare you about who to date. Even if she wasn’t easy for [i]him[/i] to get along with…she may be a totally different case for you.
If your friend gets jealous, then it’s his problem. They broke up! In my opinion, if he wanted her back, he should have told you this when you asked about her.
There ARE certain “guy rules” about dating a friends ex-girlfriend, but I don’t think this breaks any of them. I say ask her out.
