My friend moved out without saying goodbye and now she's calling me back a year later

Hello, sorry I don't speak English well. I have a dilemma. A long-time friend moved to another country over a year ago without a word or goodbye. I wouldn't have even known about it if I hadn't written to her on her birthday. I wanted to come and celebrate her birthday. She wrote me back that she hadn't lived in this city for a few months and added a smiley face with her tongue out and the sentence "I hope you don't fall out of it". It really hurt me that she didn't care about breaking up with me. If I hadn't called her back then, who knows if she would have told me about it. We've known each other for years, lately we've mostly just been texting and calling each other occasionally and we've met up about once every 2-3 months. But she doesn't even know how much I cried because of it. She wrote that she'd get back to me later. I wrote her back that I was sorry that she didn't break up, but that I wished her well :) and she didn't write back to me after that and didn't call me back for about 9 months :( but I realized that I didn't meet her very often because I always felt exhausted after meeting her and we also have different opinions, interests and actually she for example, she never even mentioned my birthday. I found that I was more comfortable without her and I've come to terms with the fact that she left like this. But she started contacting me. She wrote me some poetry for Christmas and now she's writing to me again on FB. I haven't written back to her yet and I don't know if I even want to. I'm often a weakling to people and I'll contact them when they want to talk. But they don't listen to me. Now I feel guilty that I didn't contact her and what if she needs help? Should I open it up again? What do you think?