Foot in mouth department

So...I saw a woman on the bus, whom I know slightly, and said out loud the thought that had often popped into my head when seeing her: "You look just like my Grandmother".

This was not well-received, despite the fact that the woman does in fact resemble my Mother's mother. Definitely one of those faces with the map of a particular corner of Ireland on it. Out West, I'd say. But in any case she said to me, "Well, I didn't want to hear that". This was perhaps the first time in my life I'd said something that offended someone, so I didn't know what to say (right).

I later pondered how I might have phrased my ill-advised comment. "My Grandmother looks just like you". Uhh, no.

"For a woman who quite obviously is far too young to be my Grandmother, you resemble her". Better, but sounds smarmy.

"You have the look of the West Country of Ireland, which my Grandmother also had". Huh?

"As Grandmothers go, you look just like my Irish one." Even more, huh? Also, face slap.

I really should have just gone with, "Nice day, isn't it?".