Does A Dog Ever Stop Going Into Heat When It Gets Older And If So At About What Age Would This Happen?

I have a dog who is getting older and every time she goes in heat our smaller dog bugs the heck out of her. She usually tries to avoid him or sit down when he comes up behind her. This time she is actually attacking him, so we tied up the small dog but instead of avoiding him like usual she would go lay down within his reach. So we are hoping she will quit going in heat and maybe that is why she is acting different.