<human>: Provide a brief overview of the text.

I have been in a two years rollercoaster relationship with a girl. We had several break ups, but somehow we always managed to get back together. With her I had the happiest moments ever. Before summer she broke up with me on the grounds that we have different goals in life. She wants to have a careless hedonistic life, little commitment, and have an open polyamorous relationship. Since I want more or less the opposite (some thinking about the future, eventually family, and monogamy), I agreed with her arguments and, even with a lot of pain, we broke up nicely. At this point we stopped all contact.

Two months later she contacts me, saying that she is mainly dating an older guy who is into polyamory and experimental drugs, and another side guy. My surprise was that she said that she felt unfulfilled with her love life and that she wants to get back with me. I visited her and we ended up having sex, but she said that she was afraid that being together again would be a disaster. That wrecked me emotionally. We stopped communicating again.

Fast forward another month and she contacts me again. That she really loves me, that she wants to spend her life with me, and that even if we cannot be together right now, at least we should see each other because she misses me a lot. Even having the determination of not wanting to meet her, my heart softened and I allowed her to visit me. We had sex again, it wrecked me to hear again that she wants to keep her partners.

On the one hand I think that our different lifestyles are incompatible and it is very possible that she is also in love with the other guy, so there is no way we could "solve it". On the other hand, I believe I lack the determination to say "no" to her and keep it till the end. Would it be easier if I just avoid potential damaging situations like talking to her? Last week I told her that while she has partners I won't meet her. This time I want to keep my promise, however having such strong feelings for her I fear I might fail again. How do I do it?
<bot>: Would-be Ulysses wants to forge a chain of reason to avoid succumbing to the mermaid (again).