please don't get discouraged so soon. First of all: talk to your husband. talk bout how you feel and what you would want. Ask him how he feels. Tomorrow, talk some more, and the day after, talk some more. You seem to be doing a lot of assuming about how he will feel and how he will respond. You won't know for sure until you actually ask him.
Secondly: these things take TIME. A shit load of time. You can't map it out and know what you want. Things change, you meet people, dynamics shift. Once you start down the poly path you won't believe how your thoughts and systems and beliefs will be challenged.
I'll tell you a story. When my husband and I opened up our marriage (this is what we called it at the time - I would never describe it like this now) this is what happened.
We had decided, and agreed, that we would look for another guy to have a threesome with, ideally a guy we could have multiple threesomes with. My husband 'found' them for me online, showed me their profiles, he made initial contact with the guys I fancied, then I would meet them for a drink, husband would join us IF I texted him that I was interested in said guy, we would get to know each other, and make a date for a threesome.
Wow, I never wrote about this on here before, and it almost makes me queasy to write about it now. What were we thinking?
I remember talking to one of these guys, way in the beginning, and I said 'now we would have to meet in a hotel room, for sex, because, you know, my home, that would be way too private.'
The thought that my husband would date someone? Out of the question. The thought alone made me sick.
Fast forward a couple of years. My husband and I both have relationships with others. He just came back from a week long trip to another country with his girlfriend. While he was gone, I entertained my FWB on one night, and had my lover MrBrown over for a BDSM session on another night. Right now I'm house sitting for a friend, and enjoying the time alone. This weekend my bf C will come and visit me here. Oh and tomorrow I'm having dinner with my husband and his ex GF, because she is traveling to a country I've done a lot of research on and I want to give her advice (also, I really like her).
Sometimes I think of that poor guy who was actually looking for a real poly relationship, to be told by me he could only meet me in a hotel room with my husband present.
I've come a long way since that conversation.
Be patient and stay open to all possibilities and don't rush things and don't judge yourself for wanting things a certain way at this moment - just be open to change.
early forties, straight.