Boundaries are your most important tool in this scenario. If your attraction feels overwhelming, it may be necessary to limit the time you spend in high-pressure social situations with her mother. Creating a healthy distance allows the "novelty" or intensity of the attraction to fade. Remember that any pursuit of these feelings would likely result in the permanent destruction of your relationship with your girlfriend and cause irreparable damage to their family dynamic.
This situation often signals a deeper issue within the primary relationship. When we focus on someone external, it is sometimes a subconscious way of avoiding intimacy or dissatisfaction with our partner. Ask yourself if there are elements of your relationship that feel stagnant or if you are looking for an "escape" through a forbidden fantasy. Shifting your focus back to the qualities that made you choose your girlfriend in the first place is vital for the health of your bond. Boundaries are your most important tool in this scenario
Ultimately, maturity is defined by how we handle uncomfortable impulses. Prioritize the person you have committed to and protect the sanctity of their family unit. If the attraction remains a significant hurdle, it may be helpful to speak with a therapist to explore why these feelings are surfacing and how to move forward with integrity. Reinvesting your energy into your partner is the only way to build a future based on genuine connection rather than fleeting physical allure. Remember that any pursuit of these feelings would