My ex now has feelings for me ..

So my ex has confessed his love for me after being broke up about 10 years . Our relationship was interrupted by a women that was persistent on being with him no matter what his status was . She harassed me ALOT as a teenager. (Jumped me) few kids later he decides to confess his love for me

After I’ve befriended her .. what do I do ? The feelings are mutual . Should I be sensitive to her feelings or follow my heart .