I'm seeing a few red flags just reading your question that I have to point out - "I'm ready...she isn't", "family is at the top of her mind", "she won't be in it."
The fact that the two of you have been together for at least 16 years (based on your profile ages) and excluding all others is a pretty major thing. Your wife may be perfectly happy with the penis she has at home and not want another. You may have to accept the fact that she will never be interested in anything sexually outside of a monogamous relationship. OR she may be curious but just isn't ready at this time - it sounds as if she has her priorities elsewhere right now, and if you have a young family can you really begrudge her that?
While you may be super keen to go to a swingers event, if you push her into it before she is ready (assuming that she ever IS ready) then you'll be ruining any possible chance of moving forward in the scene for both of you. She will not be in the right head space and won't have a fun night if she isn't fully relaxed and open to it. What's worse is that she will likely resent you for pushing her into it and I can pretty much guarantee that she will not want to go again and will shut down completely about anything sexy outside of your 'norm'. Don't push her into it until/unless she is absolutely ready.
Have you discussed it with her properly? If not, sit down and talk about it fully and openly - tell her about your desires, ask her about hers, and she will let you know whether she is or isn't open to it in future. Then it's up to you to decide where to go with her answer.