I am a UK player also, and Pokerstars has to prove their RNG is fair and realistic before they can obtain a license to serve UK customers.
Every poker player will run worse than they have ever done before.
I am also experiencing a downswing after a huge 150k hands upswing. I've dropped 12 buy-ins in the last 4k hands played. Hitting top set on the flop and losing to a runner runner straight. Flopping a full house and being counterfeited on the river to another runner runner. The same feelings you have now I have also been experiencing the last few days. Playing my c-game because every time I pick up AA or KK I know I am going lose to some freakery.
I have played over 3million cash game hands and during this time have experienced huge winning and losing streaks. I once ran so bad on Pokerstars I considered quitting the site convinced it was rigged. But I managed to reason to myself that I was only experiencing negative variance and will eventually ride out the storm. I did but it nearly drove me mad. I was predicting runner runner suckouts as if I had a crystal ball and could see into the future. The negative variance lasted for some 200k hands.
If you haven't run bad at live yet it's because you are running good. I ran good for 150k hands which is the equivalent of two years worth of full-time live play. I have also run bad for 200k hands.
A moderator should be able to recommend to you information on the mental side of the game. This is essential reading material which you may find very helpful.
If I were you, and I mean to be helpful here, I would refrain from sending emails to Pokerstars complaining about the RNG and your bad luck. As part of their UK licence conditions they must do everything possible to prevent vulnerable people from gambling. Those not enjoying their poker fall into that category. Just a friendly warning.