Husband (32m) wanted to try and open relationship, I (28f) reluctantly agreed and I fell in love.

We entered this relationship being monogamous and honestly everything seemed amazing. We have a couple hobbies we do together and friends that we hang out with and everything?s been fine!
My husband got a new job two years ago and meets lots of people all the time. I understand we still get crushes on people ?but we love/d each other and I expect us never to act on that. He came to me asking for an open relationship he was obviously researching it. He framed it how it would be good for me and good for him just showing all the positives about that kind of stuff. I was so secure in our relationship I figured you know what why not even though I didn?t really want it?. I should?ve stuck up for myself more but honestly maybe this was meant to happen.
He must?ve had someone in mind because right away he already had a 2 Women lined up and was seeing them. It?s just crazy we work full-time so we have our evenings to spend time together and do our hobbies together but suddenly he?s out on dates. A lot. It?s really hurt me and I tried talking with him but he was kind of manipulative and I see it now.
Anyways to the point of the story, I finally started meeting other people online and chatting, i met one man who is very very handsome and a really great guy and decided to meet up. I?ve never felt these feelings before, my husband and I kind of had a slow burn that got better with time but this is just something completely different we connect on a totally different level. The sex is better (so much passion, enthusiasm and exploring) the conversations are better(he takes an interest in what I have to say and I love hearing about what he hast to say) and honestly we seem like a better fit. I?ve even opened up and told him about this open relationship and I didn?t really want it and all the things that go with it. he confessed that he?s been waiting to see if it was possible we could be together and be monogamous.
I?m planning on leaving my husband. I?m seeing a lot of things now that I never saw before , now that I?ve been with this new man for about 5 months. My husband has been coming home more often and I think that things are falling apart with one of the women possibly the other as well. I honestly don?t even ask about it anymore which I think he is kind of sensed. He whines and moans that I?m going out too often, but I just kind of tell him the same thing he told me and do it anyway. He said he wants to talk about going back to normal.
Basically what I?m asking is what should I say to him When I break up with him? I want to be kind but let him know how I feel like he destroyed what we had and could?ve had. I really don?t want to do the therapy thing and try to save this relationship, it feels over to me. I can?t even describe how much better this other relationship is even by communication and other standards it?s just crazy. Something that felt like the end of the world turned out to be like my life finally just started?
TLDR husband opened our relationship up,I hesitantly agreed and suffered until I met someone else now I wanna leave my marriage.


Source.