If you think you want to be friends with her, accept. In my experience, many people who used to date drift away because of dissimilar interests or goals, even if it ends in a friendly manner.

She may not want to be active friends...but rather just to know that you don't dislike her. It's up to you whether you want to accept her invitation or not

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Life is too short not to love and be loved....preferably multiple times in one night.

I think men talk to women so they can sleep with them and women sleep with men so they can talk to them. ~ Jay McInerney