My mother-in-law advises me to disregard husband’s interactions with mistress

My husband and I are both natives of Ho Chi Minh City and have known each other since our school days. My home was distant from our school, and his was equally far. He used to take me home on his bicycle after school, and by the time he returned home, it was midnight. We faced many challenges to stay together. We have been married for 10 years now.

I recently discovered him texting an unknown woman, his messages filled with declarations of love and affection. I was profoundly shocked, particularly when I found photos of them intimately holding hands. Upon confronting him, he insisted it had not progressed beyond that. He justified his actions by explaining he had borrowed money from her and needed to express affection to extend the repayment period. He then committed to ending the affair and repaying the debt gradually.

My trust in him was deeply shaken, yet he maintained that there was nothing more to his relationship with the mistress and refused to divulge further details.

Aware that my husband is still living with me, the mistress has since returned to her hometown and left HCMC. Nonetheless, my intuition suggests they are still communicating. After inspecting his phone recently, I confirmed they are indeed still in contact.

I shared my frustrations with my mother-in-law, but her response only intensified my distress.

"Whatever your husband does, just ignore it," she advised. "Stay if you can."

She also mentioned that they had secured a bank loan to settle his debt to this woman. I desperately do not want to lose my family, yet their actions have caused me profound pain.

What should I do?