How to interest my baby in walking? Tips please :)

I know I'm not meant to care when DS starts walking as even 18 months is completely normal etc etc, so wouldn't admit to anyone other than on an anonymous internet forum, that I would really LOVE to hurry things along now. DS is 13 and a half months and is an expert crawler, climber, cruiser and stander, to be honest I have thought he was on the verge of walking for the past 5 months - well he obviously wasn't! :)

More than a month ago he took his first independent steps (just a couple) to much applause. I was so excited I could hardly contain myself and tried to encourage him as much as I could. For a couple of weeks I saw him practicing daily, managing 2 or 3 steps at a time before ending on his bum (but only when he felt like it, not on demand..). My MIL who was visiting declared that he was just moments or days away from proper walking. And then.... he completely stopped trying. It is about 2 weeks since the last time I saw him trying to walk :( I feel as if I did something wrong.... did he suffer a fall that I am not aware of? was I too eager, laying on too much pressure? was I supposed to help him in some way I am not aware of and now he has given up?

He used to love "walking" around while holding onto our hands since he was, like, 7 months old but now he doesn't want to anymore... when I try to encourage him to stand or walk for me he just makes his legs floppy and bends his knees until I leave him alone. Then he goes back to pushing around his walkers / cars / the dining table chairs, chasing balls around on his knees, climbing onto the back of the sofa etc etc...

Of course I know the correct answer.... I should just let him be and wait for him to show me when he is ready to try again!! But I am starting to feel sorry for him, all his playgroup and playdate friends seem to be running around by now and he is left on the floor all by himself, unable to do anything when they take toys from him etc! I wouldn't have worried so much if it wasn't for what seems like a regression in skills / interest?

Does anyone have any thoughts or ideas? Thanks :)