Since the urge is strong, on the one hand, and the realization that you should not do that is strong, also (the rational part of your OP is strong), I would make sure you use really effective contraception so that you have no chance to give in to the urge on an impulse. The Pill plus condoms would be best, given that you probably cannot have an IUD since you have not had children. There is some evidence, though, that an IUD is safe even for you - you need to read up on that.

http://nwhn.org/not-your-mother’s-iu...ks-modern-iuds and you need to read more.

In other words, you should solve the practical problem of making sure you cannot have a baby now, and once you have solved this immediate practical problem, you can spend however much time you have on answering the "why" part of the thread's title.