Oh Goddess!

A friend from my college days just got me on a Whatsapp thing, in a group, and invited me to her <whatever> birthday party in a couple of weeks. On a little boat, moored in a wharf not far from where I live.

I walk with a cane, I have a blue badge for my car, etc, etc. I properly really want to go, but a big chunk of me is going, wait? Clamber over several boats to get to hers? And then get drunk and probably stoned at a party , and then *clamber back to land*?!

I can see me drowning in the harbour before the night is out!

Is there a socially acceptable way of getting out of this?!