Its a classic dilemma and one which is hard to resolve. The simple truth is that if you try to 'drag' her in there is a good chance that she will respond badly and not only back away from the lifestyle but possibly also back away from you, the wierdo who tried to force her into something she did not like. Ok, there is also a chance that she may jump straight in with both feet and become a staunch lifestyler but I think that possibility is a lot less likely...
So, you need to be careful and make sure that she is aware that there is a choice at each step and that you will not think any less of her if she chooses not to get involved. You may also have to accept the condition that if she is not interested then you have to reduce your BDSM activities to prevent her from thinking that you are cheating on her with 'some skanky kinky tart' (trust me, this is how vanilla women think when their man has a 'hobby' they do not understand or like. They are petrified that he will elope with someone who understands their hobby better and this is not an entirely unjustified fear).
Small steps and lots of communication is the key. I have yet to meet a woman who is not interested in some aspect of BDSM. Many vanilla women will readily agree to some light spanking and a bit of light bondage and this is the shop window you can use to draw them further in. The difficulty usually comes when you try to introduce nipple clamps, ball gags and enemasKeep it light and fun...