If you have a big decision to make and you look to your wife for her opinion, one of three things may happen. She says it's important to her and really wants to do it, she says she doesn't like it, or she says "I don't know – what do you think?" The third option can drive you mad. "Arrrgh! Just tell me what you want!"
Of course this is because we men innately want to please our wives. It's in us. That's why we are directed by God to love and serve our wives – because that's what ultimately will make us happy. But in this case, what the heck are you supposed to do? The reason it is maddening is that you want to please her, but she won't tell you what she wants. You are afraid of making a bad choice and disappointing her. So what's going on here?
Besides loving and serving our wives, we are to lead our households. And wives innately know this – it is in them (please don't take offense, ladies – remember the perfect circle of the marriage relationship – we lead, but we do so by serving you). So in this case, she may be looking to you to take the lead and make the call.
I suggest that you tell her that you are going to make the call, that you want to do what is right for her, and that you need her to respect your choice – because she is not giving you any feedback. Then make a decision that is in her best interest and stick by it. (Unless she is really upset – then tell her that she needs to communicate with you because you ultimately want to please her – unless it's a bad decision for the household – like something you cannot afford, etc. – this is not intended as a blanket statement) But otherwise, stick to your decision and follow through.
In a nut-shell: when she vacillates, she is looking to you for leadership. So lead. This will make you more attractive to her – when you're more attractive to her, her libido will improve as a result. Women want their men to please them, but they also want their men to be men – to be leaders.
Note: yes, I know there are plenty of women leaders, but in a household situation like this, the man is being called upon to take the lead and make the call – so he should not pussyfoot around – the husband should make the call – that is the point.