How would you react?

This customer that walked in at work asked if I had a boyfriend and I said yes, and he asked how long and I said 6 years. He then said wow that’s a long time and he hasn’t proposed? And I said nope he hasn’t. Then he said “ why milk the cow if you can get it for free, well you’re so bubbly and nice i wonder why he hasn’t. He’s going to miss out on something nice.” The first sentence made me feel kind of bad, because doesn’t that saying imply im giving him “benefits”? Like sex? Idk i was really embarrassed but didn’t say anything.