lying to herself by disallowing her natural feelings
Its not that simple. For instance, some people have a propension for violence. Its their natural inclination. They don't give into it cause they know its wrong. Its not because you don't give into natural feelings that you are lying to yourself. It simply means that you are keeping natural feelings under control to uphold your values.
In the case of your girlfriend, she is either a) lying to herself by staying with the JWs who are adamant about values that she does not share or b) she is willfully breaking her own values. The second option is the scary one. When someone willfully breaks with their own values, then they are at the mercy of they desires and this could have disastrous consequences to them and their loved ones. I underlined willfully as this is what it is when someone does an action that violate their values over a long period of time. This is not the same as a one night stand where someone temporarily give in to their baser instincts; it happens! But not in the case of your lady. Sorry to be so blunt about this.