Confused About My Ex-Girlfiend?

My ex and I broke up about a year ago. It absolutely crushed me, we had such a beautiful relationshp. Everything was wonderful and then she came home from a business trip and wanted out of the relationship. She was my world and I would do anything for her. Every single little thing about her I adored. I’ve been in quite a few relationships, hell I was even married once, but I’ve never been in love like that. I was so crazy about her.

Since then I went through therapy and did some soul searching. I tried to forget her and I thought I did. I found a wonderful sweet girl and I’m in a relationship with now. She treats me like a king and I care for her a lot. Things have gotten kind of serious recently and her lease is up and she is going to move in with me to save some money.

I thought I forgot my ex and was over her. She recently emailed me, her grandmother recently died and I’ve been going through rehabilitation for drug addiction. I am 40 days sober now, which is the best thing I could have ever done for myself. She wants to see how I’m doing and talk. She wants to go grab lunch next week, and I don’t know what to do. I know things are different with girls and she probably just wants to grab lunch, but I’m worried that I may do something stupid or regretful.

I don’t want to hurt the girl I’m with and I don’t want to go through that pain again. Since she’s emailed me I keep thinking about all of our great memories. I’ve found myself playing songs that remind me of the love we once had. I am still head over heals in love with her.

My questions is what should I do? How should I go about this? I am very confused.