My Girlfriend and I have been fairly sexually active for about a year now. Randomly about 6 months ago she got a UTI which turned into a kidney infection. She was fine for awhile but she started to get random utis. Eventually it got to the point that even if we had the most safe and tame sex she would get an UTI EVERY time. I dont use spermicidal lubricated condoms or anything. We did introduce astroglide into our sex lives ROUGHLY around the time when all this started. Is it possible that the lube is causing this? I am concerned about her because she can barely have fun anymore. Her vagina as a whole gets pretty sore even with mild sexual activity like foreplay only (the outside and all for a few days after).
Ps. There is no chance of STDS on either end so that is not the problem.

I'm not sure about the astroglide, but I was getting UTIs nearly every time my husband and I had sex and I had heard that I could get a prescription for antibitotics to take after each time. I did not want to be on antibiotics for the rest of my life, so I searched around and found another option in a dietary supplement called d-mannose. It's actually just a kind of sugar, but the idea is that it grabs onto e coli molecules and takes them off of of the walls of the urethra and they get flushed out. It actually worked and I haven't had a UTI since I started using it, though it did take some time to fully clear up the first full blown infection.

I'm sorry to hear this, but you'll be happy to know that I went through the SAME exact thing and I found an answer....you may not like the answer, but hey, such is life.
First I went to a naturopathic doctor. She had me keep a food log...write down everything I ate and how I felt every single day.
She noticed that I would have symptoms when I ate certain things. She asked me to stay away from those things for about a week. We went through trial and error until we finally found the culprits. For ME, I was reactive to anything with vitamin C, corn syrup and a bunch of other things. Then, I did a candida cleanse, which helped soooo much. Then she put me on detox drops for drainage. After each treatment/remedy, I slowly felt better. Basically, it was my body just needing a "tuneup"/cleaning.
The last time I had a UTI was about 2 years ago and loving life and sex...
Good luck.
Let me know if you have any questions.