My mother opposes my marriage to Japanese girlfriend as she wishes to live with me

At 27, I moved to Japan a year ago, where I began dating a Japanese woman and now contemplate marriage. However, discussing this with my family revealed my mother’s objections. As the filial son among the three siblings, my mother expects to live with me as she ages. This led to her reluctance when I introduced my Japanese girlfriend, fearing my permanent relocation to Japan, limiting her visits and causing her distress.

I am considering staying here for another five to 10 years, or perhaps longer, and wish to marry. Yet, I love my mother and am uncertain how to manage this situation.

Has anyone faced a similar dilemma? What should I do now?