My wife and I have been married for close to 4 years now, together over 8. Lately, our sex life has been feeling kind of stale to me. The sex is still good when we have it, and we're still having it frequently, I'm just getting a little bored, and wanting to try something new. Her natural inclinations are very vanilla, so it's generally up to me to instigate new things. She understands that I want a little more excitement, and that it's important that we're both happy with our sex life, so she's willing to try out new things, she's just not good at instigating them. I'm very interested in dominating her, both because I'm aroused by the control aspects of it (she can be a very stubborn woman sometimes), and because it let's me push her to try things she might not normally try. I brought the idea up to her, and she said that she'd be willing to give it a try. I read up on it some online, and we had a discussion about it before we started anything. We set up a safe word, and discussed hard and soft limits. We started out fairly slowly, trying some light bondage, short dom/sub sessions, light discipline, and some sensation play. We had tried a few short sessions, and things seemed to be going well. Then we made a stupid rookie mistake. I was trying to train her to deep throat better and neither one of us had thought to come up with a way for her to stop things non-verbally if she was uncomfortable. Things went too far for her, but she didn't say anything immediately. After that, any time I'd bring it up trying a session, she would say she just wasn't in the mood, or not right then, maybe later. Eventually, she told me what had happened, and we had a fairly long discussion about it, and about what kinds of things she's like to have happen and what she wouldn't. We fixed our earlier mistake, and she was a bit hesitant, but agreed to try again. We have had a couple of short sessions since then, and it's seemed to go okay (no use of the safe word/action, she said she was fine afterwards), but she still seems very hesitant about the whole thing. We've discussed the idea of trying for a longer session, lasting a few hours, or maybe even all day (not an all-day sex session, but requiring her to be submissive for longer periods of time, and outside the bedroom) and the idea that it might help her feel more comfortable with the idea if she had more time to get comfortable with it. Is that a good idea? Or are we heading for trouble again? Do you have any other suggestions about how to get her more enthusiastic about the whole thing? Things I could try to bring her out of her shell a little more? Do I just need to give up on my fantasy because it's not for us? Any advice would be much appreciated.