Yo Andy, helicopters are a pain in the butt because they follow no known rules. We had to put up with them at Wycombe Air Park. And when on approach in a glider, one hasn't the choice of going around or taking any dramatic evasive measures.....fortunately they were not bolshie crop spraying types, intent on completing their spray jobs rather than keeping their incredible wash clear of other airport users....
Which is the problem at your place. Have a chat with the management of the flying school, see if you can avoid helicopter traffic next time you fly. Wake turbulence is definitely to avoid. Don't fly too close to the rump of a 747 either, for that matter! (but at least these don't fly backwards!)
Crosswind landings can be tricky as well. But don't let this scare put you off, I think it shows commendable caution and a sense of your limits, which will be cured by experience.
Actually, are you too far away to visit any other flying school? which might have a quieter environment? or even, forgive me for mentioning it, a gliding club? in other words, as you are taking a break from flying anyhow, sample something different, and a different place, when you are ready to start flying again.
Don't worry, stay happy, have fun, that's what its about, really!