The London Book/Literary scene - how to get involved?

[Legacy]

Have moved closer to London (30 mins by train/commuter belt) and adult kids have left home so I have more time to pursue hobbies and interests.
I have always been interested in books and literature, dabble a bit with writing, love theatre etc.
I'd love to get more involved in the London book/literary world, but finding it hard to do! I was a member of the RSL and went to a few events on my own, similarly with the Southbank Literature Festival, but they're not sociable events and there was no real way to meet people/ chat etc.

Any ideas of clubs/ courses etc which might help?