Tension with loved one

I am 34 widow love with 41 yr unmarried person,we love each other want to marry, but his mother ( mentally sick ) is threathening if he marry me she will kill herself becz i am widow & having 11 yrs old son.From this threathening he is not ready to marry me or anybody then me. and we are keeping all types of relations also , same way he is ready to love & keep this secret relation till his end of his life but not ready to marry without his mom permission. Even i too love him so had bed relation also with him past 6 months.. But now a days i am feeling very much depressed by thinking this type of life , becoz i am having son , this society i am very much afraid thinking of bad name & my son future. he is not ready for marriage or re-gister marriage just to hav & to give all support he is ready( mentally , physically , finacialy ) he is ready to give.. but no marriage. pls give me suggestion.