If she has trust issues and is going through all these rough relationships, maybe a phone call would mean a lot. You could try making the first step, and then let her know that she needs to make the second step when she's ready... something along the lines of "Hey, lets get lunch. Oh, you can't? That's okay. Just know i'm always here for you if you need me. Let me know when you have some free time or just need to talk." Something along those lines. I would try to keep communication open with her if you can. Also, people do get busy. I have a friend that I used to get lunch with every week too. But then life got crazy and I think we cancel more plans than we make. It's hard, but friendships really are worth the work. Good luck!