Coming out of hibernation to back you up, Dr. Cox.
For what it's worth, as a soon-to-be EM physician, we get plenty of return offenders ourselves. It's hard to avoid them. Though I'd argue that in the ED, the return patients are not the ones you actually want back...(think chronic pain patients who come back for their dilaudid). And also, plenty of infectious diseases.
OP, I'm actually not sure what you mean by being ok with infectious diseases but not wanting to treat them. That's kind of what we do- if it's there, we're expected to deal with it. I'm not a huge fan of ID either and hate spending twenty minutes debating the merits of different kinds of antibiotics and what bugs they cover, but there are ways to get around that no matter what specialty you're doing (unless you're internal medicine, in which case that's part of your job to some extent). Eventually you become pretty good at recognizing patterns and knowing which antibiotics to use in which circumstances without too much drama- and if it gets more complicated, you can always call ID for help. OB/Gyn has its share of ID (plenty of STD's and vaginal discharge nastiness to deal with) so you can't avoid it there either.
Also, for all of you surgery haters, technically speaking Ob/gyn is a surgical specialty. They are surgically trained. Many gynecologists further specialize in surgical oncology and do essentially what Dr Cox does but lower down (same amount of follow up, same amount of clinic), many gynecologists do urogynecology and work on bladder issues/incontinence and such and arguably have a lot less follow-up than surgical oncologists like Dr. Cox do. If you do obstetrics, and you have your own private practice OB patients, you obviously see your patient a good amount during the pregnancy- infrequently at first, then frequently toward the end of the pregnancy, then you deliver, then maybe you see her once after the delivery, and then your job is technically done. You're not always the gynecologist your patient keeps later on for all well-woman checks, and depending on how busy your practice is, you may not have time to do full-time ob AND benign gynecology (nor may your malpractice premiums handle that well). On the other hand, the OR has a lot less infectious disease risk than clinic, especially when it comes to ob/gyn.
So what I'm saying is, no specialty in medicine is perfect, and you won't realize what fits until you're elbow-deep in it and can really see yourself in the middle of it. You may discover that dentistry or psychology is for you after all. You just never know.