Hello and thank you for posting your medical question on E health forum.
Yes, it is possible for either partner to become infected with HIV through performing or receiving oral sex with a person infected with HIV.
If the person performing oral sex has HIV, blood from their mouth may enter the body of the person receiving oral sex through the lining of the urethra, vagina or cervix; anus; or directly into the body through small cuts or open sores.
If the person receiving oral sex has HIV, their blood, semen (cum), pre-seminal fluid (pre-cum), or vaginal fluid may contain the virus. Cells lining the mouth of the person performing oral sex may allow HIV to enter their body.
The risk of HIV transmission when either of the partner is infected, increases with the presence of open cuts, sores, in the mouth, presence of other STDs. The risk increases also if the person receiving oral sex ejaculates in the mouth of the person performing oral sex.
Transmission of Infection via oral sex with a partner can be prevented by - using a latex barrier. Ex. a condom (latex or polyurethane) on the penis; or a latex barrier between the mouth and the vagina (a natural rubber latex sheet, dental dam, or a cut-open condom that makes a square or a plastic food wrap.
You might consider consulting your GP for further advice and additional information on tests for HIV. Getting tested for HIV would be helpful in your case.
I hope this helps you in your health care decisions