please help

Hello, I'm going to get straight to the point here. for the past 6 month it has been really hard for me to have sex, anything penetrating my vagina burns, I had 4 yeast infections 4 month straight. I've been tested for all sorts of STDs and infections all coming back negative. I've been to the obgyn, they said it doesn't look unusual, I've even been tested for diabetes and pregnancy those came back negative too. if anyone has had a similar problem or has any idea how to go about this please share, I'm losing all hope and feel like im a drag to my partner( who has been really supportive)