Issues with a close friend

This dear friend of mine has been a huge part of my life for the past year. She’s helped me through some incredibly dark times and we’ve grown really close because of it. About 8 weeks ago, she told me she needed a break from our friendship. She said that she was so focused on me that she was ignoring her own mental health. It hurt like hell, but I respect what she wanted and took some time to work on myself. I finally got into therapy and made some life changes. A few weeks later, we have this amazing talk and everything seems good between us. She flies to see me and we spend a week together. But now, she’s saying she needs another break from me. And I’m really struggling to understand why this is happening again. I love her so much and I want her in my life, but I’m starting to question if this friendship is healthy for me anymore. But then I feel guilty thinking that because she literally saved my life and was there for me for 6 months straight.. day in and and day out… so I guess I just don’t know what to do or what to think. I’m heartbroken. Any advice would be greatly appreciated.