Ok, I get frequent Urinary Tract Infections - HELP?

They are not fun. I have been to 2 specialists and my regular Dr. all say nothing wrong here take the antibiotics. I know the hygene rules, have had a hysterectomy, quit drinking pop, have only 3 cups of coffee a day, drink at least 8 gles of water a day and I'm frustrated and tired of recurring infections. I am taking a multi vitamin, cranberry tablets, B complex vitamins. The last straw - my regular Dr insisted I get yet another urinalisis and it came back the same as the others, he said you must be atrophy. I know a lot of you have the same issues, what triggers your attacks. What do you do to avoid them? Please help!