My gf (28F) and my best friend (30M) confessed their love for eachother and it ended our relationship. Now I'm (29M) alone on Christmas while they're spending time together.

2 weeks ago I came back from a work trip. I was gone for 3 weeks and she didn't even get off the floor to welcome me back. We've been having fights about me feeling like she hasn't been as affectionate as I would like, and how she feels like she can't express herself and be the free spirit she wants to be.
We flirted with the idea of messing around with others but never committed. I've always been in a "traditional" relationship, but with her I have been opening my mind to experimenting with others. I just have insecurities and it's been taking time to try to get over them.
It all came to a head when I got back from my trip and told her it made me sad that she didn't even seem to miss me. We ended up fighting and talking about breaking up again, ever fight we have usually ends up with her asking "why do we keep doing this, we should just break up." After things calmed down and I tried to tell her i want to be with her, she agreed and asked how I would feel about opening the relationship to date others. I didn't really know, and eventually after some discussion and questioning from me, she confessed to having some feelings for my best friend. That threw me through a loop, but I could sense they felt some type of way. The way she talked about him, things she's said. I had a feeling.
I shouldn't have, but I ended up asking him how he felt about her. Told him to just be real. He confessed the same. Said he didn't want to hurt me or make it seem like he wanted to steal her. He was planning on not saying anything and just getting over it. But now that we talked about it, maybe we could do a polyamory thing and all be partners. He doesn't want to hurt anyone.
I don't know why, but I ended up telling her how he felt. They talked and told eachother they loved eachother, and that they could see all of us together as long as it was what I wanted and I would have to be the one to decide when to have that conversation. I spoke with her the next night and I didn't have an answer. How could I. We just went from flirting with swinging, to talking about opening the relationship, to now wanting to start a relationship with my best friend, while also knowing we haven't resolved these issues with our own relationship. It's intriguing, and I could see it working out, but we would need toneork on our relationship before anything. So we mutually decided to break up while we figured out what we truly wanted. She told him she was stepping back from everyone and soul searching herself.
He's been talking to her every day. They're best friends. She's staying at an airbnb with a family member while shes moving out, and he's gone to visit them almost every day. He asked me for my blessing if he pursued her because he's truly in love. Like an idiot I gave it to him, it's not up to me what he does it's his life and who am i to stop someones happiness. But it ****ing hurts and i dont know if i can be around to see him and her together. The 2 of us went to a party and he was on his phone all night texting her, it made me sick to even look at him. This morning he left to go spend Christmas with her and her family, so I ended up going to another friend's house just to not be alone. They came by to exchange whatever gifts her and I got for eachother and they left together again, he told me he'd be back later.
I feel betrayed. If you're really taking a step away from everyone then why are you seeing him every day, talking to him all day? If you're my best friend, why are you choosing to spend all your time with her knowing that we've been having issues and I'm hurting and would like the support of my closest thing to family? So here I am. Alone. Because I opened up this can of worms and can't close it again. I feel like I just lost both of them to eachother.
**** relationships. **** the holidays. Thanks for reading.
TL,DR; Gf and best friend love eachother. Not sure if I want polyamory. We broke up, they're spending time together away from me. FML


Source.