I have been breaking out in blisters starting in my mouth and ending in my vagina

I have been breaking out in blisters starting in my mouth and ending in my vagina. I have had this problem since I was 11 and I'm 29 now. I've been tested for herpes and it always comes back negative. When they first started I had never even kissed a boy. It has gotten so bad I have been hospitalized. The Dr I saw as a child until I was 21 always said it was from my Crohns and PCOS , when I get stressed or have a period they come on with these two. Now that I'm grown and have to see someone else they say this isn't so. I have been sent to a dermatologist and ENT and the tests they have done have came back negative. I have now had them for 7 weeks straight and it keeps getting worse. Has anyone else had this problem and could give me a answer to what may be going on? I have a little boy who I can't even play with because of this. I stay in bed all day because it hurts so bad. Please help!