Help needed with relocation after breakup

[IcedCherry]

I'm a FTB and recently broke up with my partner, who I'd spent a year looking to buy a house with. He wanted to live in Surrey, where his family live, and it worked for me commute-wise. But now I'm looking for myself I'm more open to locations - just needs to be commutable to Canary Wharf for 2-3 days a week. But I'm finding narrowing down an area overwhelming. (I'm not originally from the south and not familar with the commuter belt at all). Now I'm flying solo I have a budget of 300-320k, and feeling a bit disheartened!

My requirements are:

1. I'd prefer to live somewhere near to good parks/safe walking routes (I'm a keen runner and have an energetic dog).
2. Walkability/cyclability to a decent high street with maybe a small supermarket/shop, pharmacy, PO, cafes etc, would be good if possible
3. I DO NOT want to live IN London
4. House, not a flat.
5. Near a station with a train commute of around 1 hour and 30 mins one way maximum (I mostly work in Canary Wharf area)

Any suggestions massively appreciated. Finding somewhere with good outdoor space where there are homes in my budget I'd what I'm finding hardest I think.

You could afford a house in Tring. Pretty little cottages, courtyard gardens, occasionally with parking for one car. Nice high street. Easy access to Tring Park for dog walking / running. 40 min-ish to Euston.