When both partners with HIV engage in unprotected sex, there is a risk of transmitting different strains or developing drug-resistant forms of the virus. It's important to always practice safe sex and use protection to reduce the chances of spreading HIV or other sexually transmitted infections (STIs). Additionally, regular testing and proper communication with healthcare providers are crucial for monitoring your health status and managing any potential risks. If you have concerns about this situation, it would be best to discuss them with a medical professional who can provide tailored advice based on your specific circumstances.