Well, I'm glad it's no longer a personal concern for you, Jilly, but it's still an interesting scenario.
I mentioned it to my husband, when you first posted it, and again this morning. He said that things just change when one marries, or finds oneself in a committed relationship. It's not just people of the opposite gender, who one cannot see so much, it may be anyone. Though it's fine to keep one's friends, the 'couple' relationship will change those friendships.
And he felt that it depends, if going hiking together, who else would be there, how long the venture would last, what sort of place one would be visiting, etc.
"The secret of success is constancy to purpose" - Benjamin Disraeli.