I had a sexual relationship with a lady that I met on the beach. This was about 5 years ago and the relationship lasted several months. She was in an unhappy relationship so I became her secret sex partner. Although I never communicated it to her I had developed some feelings for her. Over time I began to feel uncomfortable with this arrangement. It seemed unfair so I stopped answering her calls and avoided her at the beach.
After 5 years she shows up at my door yesterday. She has since ended the unhappy relationship but guess what?

She is now in another bad relationship. We spent about 5 hours doing nothing but socializing. The moment she walked in my house something came over me like a trance. I am madly in love with her. She told me she would be back in a few days. So unlike the last time I plan to communicate my feelings towards her.
Questions:
Am I making a mistake? Any predictions on how she will act?