"Nothing bad happened we both just went our separate ways and now she's a really successful writer and I'm still trying to sell my stuff. I don't want her to think I'm just calling because she's successful, because I'm not."
Why are you calling? That's the first thing to get clear on. Once you know why you're calling you'll know what you're going to talk about and it will be clear that you're not calling her because of her success.
But the question was, "What's the best way to start the conversation..."
And the answer to that is with an authentic compliment. Well let me take a tiny step back. The first thing you want to say is, "It's been such a long time. Have I caught you at a good time?"
If she says yes, then give her a genuine compliment. That's always a great way to start the conversation.
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