Hi. I completely agree with you. It's sadly a very similar story all over London and beyond. I see a lot more people on the streets now than i did a year ago.

I think there's a shelter in Lewisham and there's Streetlink, which is a number to call to report someone you're concerned about. Here's the website: https://www.streetlink.org.uk/

I haven't met the lady in the subway but my partner has mentioned her and he bought her a bag of food a couple of days ago. It's good to know others, like yourself, are looking out for her too.