penile abrasions/lesions accompanied by groin rash

It is now the middle of Decmeber.  At the end of September I started dating a girl with whom I have been sexually active since. Right before i met her, i noticed a fungus growing on my pubic hairs on and around the bottome of my testicles.  The fungus (or whatever it was) was yellow and could be scraped off the hairs.  It also had a strange odor. Without seeing a doctor, it treated that with Clotrimazole 1% cream for maybe a week, 2 at most.  Also trimmed the hairs, and that seemed to take care of any visible fungus i could see.  

About a week after my first sexual encounter with this girl, i noticed two red spots/excoriations on my inner thighs, right next to my testicles, one on each side.They were about 5 millimeters in diameter. They were not raised. The periphery of each spot seemed to have dead skin around it.  When i noticed these, I made a visit to my internist. He didn't think it was any type of STD and  thought it was realted to the fungus i had and tentatively diagnosed it as folliculitis.  He prescribed me Cefalexin  500 mg three times daily for 10 days. I asked him if this could be cleared up using antibacterial soap, and he said possibly with thorough, diligent scrubbing.  Not wanting to take uneeded antibiotics, I tried the antibacterial soap approach and didn't pay too much attention to the area until  the last week of October.  

On the Friday the 30th, however, I noticed that there were two red, tender lesions about the same size (maybe slightly smaller than those on my thigh) on the shaft of my penis (about the diameter of an eraser head), right below where i am circumcized.  They were sensitive to the touch. And they were not raised either.  At that point i started taking the Cephalexin.  The next night i had unprotected sex with my girlfriend. And on Sunday morning i noticed that i had about two more lesions on the shaft and the skin right under the head of the penis on the bottom side showed signs of abrasion, which later turned into what looked like a small cluster of pimples that scraped off easily and blead very slightly when they were scraped off.  This was when the simptoms on the shaft of my penis were at their worst and most sensitive.  The next day (monday) I noticed that i had 4 small bumps on the head of my penis. They were about 1 millimeter in diameter and in close proximity to one another. At this point the lesions on the shaft were present but had developed a whitish scale on top of them, which flaked off easily.  I made an appointment with a dermatologist the next day.

When i went to see him, he said the bumps on the head could (but he was doubtfull) be herpes and didn't give a clear diagnosis for the lesions.  At this point, the area on my very inner-thigh had become red (about an inch diameter) from the fold of my skin in-between my testicles outward through my inner-thigh.  It seemed (and still does) like one blotch of redness surrounded by red spots/excoritations, with no clear demarkation.  The dermatologist didn't give a clear diagnosis of the lesions or redness at that time and said "we'll call it folliculitis for now".  He prescribed me Evoclin foam for the bumps on the head of my penis and fluticasone propionate for the lesions on my shaft and redness on my thighs. He told me the Cephalexin was pointless and i could discontinue it then and I did.  And I got tested for HSV-2 antibodies.  The bumps on the head of my penis went away, but the redness on my thighs by my testicles persisted.  The lesions on the shaft of my penis seem to heal somewhat, but not completely. Or they seemed to heal but small (up to 1 cm as small as 3 mm) blotches redness and sensitivity have still persisted. The HSV-2 antibody test came back negative.  

But 3 weeks after that (end of November/beginning of December) the redness on my inner-thighs had gotten worse and red spots spread to the pubic area above my penis. Scaling lesions had appeared sporadically after sex around the base of my penis. There was a whiteness on top of the redness in my inner-thighs.  And my tesitcles iched like crazy.  I went back in to the dermatologist.  I got tested again for HSV-2 antibodies to rule out a first outbreak senario, and that test came back negative.  At this point, i discontinued the Evoclin and fluticasone, and the dermatologist prescibed me Naftin to use twice daily, which i have been using for about 3  weeks.  He said it was some sort of yeast infection.  That took care of the itching but the blotchy redness on my innter thighs has still persisted.  And he said that the irritation on my shaft was just skin sensitivity and gave me otc moisturizer lotion.

I saw him for a 3rd time just the other day and he gave me another perscription for Naftin and Epicream, to be used once a day each. I also did a skin scraping, but the dermatologist told me not to hold my breath because my symptoms probably aren't bad enough to yeild a good/definitive result. This morning i masturbated and noticed that a blotch of skin had rubbed off, revealing about a 1 cm patch of redness and tender/irritated skin on my shaft.  

I beleive what ever is going on on my shaft is more than just sensitive skin and is related to the other problems i'm having.  I have masturbated much less gently and have had much rougher sex earler in my life and have never had symptoms like this.  And im not masturbating or having sex excessively.  

1.) Do you have any idea what this could be?  Do you agree with my dermatologist that this is just sensitivity?  Is it the same as the rash on my inner-thigh?

2.) I also noticed that, Naftin is indicated for tinea infections, which i do not beleive i have because they are characterized by clear lines of demarkation around the periphery.  Do you think this could be a tinea infection?  I asked him if this could be a candida infection. He said maybe, but the Naftin should help with that too but naftin is not indicated for candida infections and i have found no evidence of its effectiveness against them.  Do you think this is a candida infection? Is naftin an appropriate medicine for the sypmptoms i've described?  If not, what is?

3.) The doctor has also told me each time that he does not beleive what i have is contagious and that he sees no reason for me to stop having sex.  Is it alright to keep having sex? That being said, sex does seem to exacerbate my symptoms about 50% of the time.  She got tested after i told her about this and her tests came back negative.  And i had a comprehensive test done at the begining of the year, before i met her, after having sex with someone else, and those tests came back negative.

What do could be wrong with me?  What can i do to get rid of this?