mono and poly
im new to this site, and i need some advice.
i have been with my partner for nearly a year, and before we got together, she told me that due to her past relationships, she didnt want to miss out on any opportunity that present then selves, including one night with a beautiful soul. it started out with her bisexual thoughts and just wanting to explore with a woman. so now i feel ready for the moment she wants, we have just got our own house together and starting our life. we are engaged. about 3 weeks ago she meets this guy who is just backpacking through our town and she told me she has a big crush on him. he is also a dear friend of mine as well and we hang out all the time. she asked me if she could kiss him and i said of course. so being a woman, she has tried very hard to make it romantic. we all went to the beach one night with his friends that he is travelling with and my partner and him dissapeared for a nice kiss. at that moment i felt i wasnt ready. i have a past that involves people i love leaving me, including my father due to cheating on my mother that i never really got over, and my ex-fiance who i cought kissing my best friend. i know it is my problem i feel like this but it is very hard for me. that night they kissed, my partner didnt enjoy it because i was on the beach and she was thinking about me. she told me the next day that she wanted to explore sexually with him. my stomach went really cold and i felt really upset. i was thinking that im not good enough for her that she has this need to sleep with this guy. i did ask her to wait till i was ready at the very beginning, but you cant help meeting these people in your life. she went out one night with him and was laying on the beach and we are very honest with eachother and tell eachother everything. he asked her to stay on the beach that night, but she told him she promised to come to me that night. she came home to me to see that i was a mess. i felt so hurt and was crying all night. i'd never felt this much pain before, and the shit thing is when im with someone for a long time, i can start to understand what there thinking and doing. she dosent like that by the way. i told her that i am not ready but at the same time i tell her to do it and get it over with. so then there comes a third time to have this moment. that is what really upset me. she talks about living in the moment which i understand, but she keeps wanting to see him. that night he told her no because of me. he dosent want to hurt me, even though she tells him that im ok, he still dosent understand. she was really upset and realised that she missed out on an opportunity because of some else. thats the whole reason why she wanted to live this way in the first place. when she rang me and told me, thats when i knew she was falling in love with him. and she told me that i was right. so the first time we go through something like this, its happend to be the worst way for me. i know if i want to live this way ( not poly just in the moment ) i need to be thrown in the deep end, and thats what happend. so now it is hard for me to see them together knowing how she feels about him. because she is honest, she did tell him how she felt and he told her that he dosent feel that way, but we both know that he only said that to look after me and to look aftre him. so know we're starting to understand that she might be poly, but i cant live like that. i said that she needs to have some space to think if this is want she wants do, but i know i cant do this now. im not ready yet and i havnt healed yet, and i dont think the best way for me to heal is put me in the same situation.
i dont know what to do. i dont want her to go but i cant live like this right now. she told me she dosent want leave me but she also cant miss another oppotunity again. we thought he was leaving soon so i started to feel ok about the whole and knowing that nothing's going to happen know. i just found out that he has decided to stay and now im really worried that she might want to start seeing him. if this is not for me, do i stand up and say no or i cant do this now, or should we find other people who understand us. we love eachother so much and i know she will never leave me, but when she found out that she was in love with him, she spent alot of time trying to make a choice.