Well, two things that stand out for me when I read your last message.
First, I remember many times my ex saying he was okay with something when he was not, and it took me asking him point blank what was going on. Actually, the last time I did that, I said, "Okay, that's it. I can't take your crankyness anymore. Why have you been so pissy all weekend?" And that's when he told me he wanted a divorce! But can you imagine if we had kept on going that way without talking about it? The resentments would have really piled sky-high!
You want to nip such potential problems in the bud, before they are become big problems. What about saying to your husband, something like, "Honey, I appreciate that you tell me to do whatever makes me happy, but it seems like there are some things you are not saying. I feel a little dismissed when you don't want to talk more about it and it makes me wonder if something really bothers you about my having a boyfriend. And whenever I go to see him, you are very grouchy. I think we need to get some of this out in the open. What is going on with you?"
The other thing is the date nights with Hubby. Yeah, yeah, so he gets lots of your attention, but is it special and romantic, like the hot dates you have with the bf? You don't have to spend money -- a stroll through a park is free -- but it is important that you set aside time to romance your hubs and give him focused romantic/sexy time for just the two of you. Consider how much he's giving you by being okay with poly. It's only fair that he be treated very special because of that. I believe that is the biggest mistake most of the married couples make when they come here and talk about problems they have with poly; they forget to romance each other as much as they do their other partners. It is an oversight that has huge impact.
This reminds me of how one member here, Sagency, describes how he approaches poly with his monogamous wife (in the quote below, he calls her "my mono"):
Beyond talk, you must have action. I make a point to translate any NRE or potential NRE that I feel for someone into energy that my mono receives. Thus, any relationship or potential that comes up causes her a direct benefit. Thinking about how delicious someone else adds to my own hunger for my mono. Beside the obvious benefit, this reassures her that she is and always will be a part of my life. Frankly, the influx of NRE reminds me that my first... relationship also deserves wooing and fun. One of our simple rules is that when either of us comes home, the coming home person is responsible for seeking out the other and giving them a kiss. It's a simple thing, but it constantly reminds us to connect. Even when I give energy somewhere else, I always try to remind my mono how important and attractive she is. Too many times I've seen polys let NRE blind them to the lovely they have right there already. The NRE may get more E, but that no one gets left out in the cold.