Thanks, I'm looking for recommendations on portals/websites where part-time/freelance work is advertised. Basically, how can I find this type of work for my skills. Between my start-up and this search, I don't have the time to learn more skills.
I can quickly comment as I was in the same situation not too long ago. I was a semi-quant in a fund in London until recently. I stayed from the intern stage to the very top. I spent my entire time working. I hated London with a passion, it's a cold city where people are cold, the weather is cold and wet, the food is terrible, never made any friends there, you're expected to join the rat race in short. It has a huge impact on you if you don't like because you're reminded of this every day, you may be thinking of other places where life is not like that, that your life is running out getting a paycheck. I'm not sure if this is your experience and I talk for myself, but maybe it is. Also I wouldn't think of things in terms of optimising career/money. These things are only good if you're happy and it doesn't sound like you are.
Here's what I've done: I left (I left far far). Life is too short. Quant skills can be applied in various things, including startups. I would suggest looking at Cambridge because you cannot leave your partner apparently. Cambridge has a bunch of funds, but also has a lot of startups working on interesting projects, you should have a go and visit the place. Things are greener, nicer, people are calmer, and you're 1hr away from your partner. Good luck.