I did my first JY holiday (Americas Golden West) about a year after losing my girlfriend and absolutely loved it, done 3 more since, one in America and 2 in europe and would recommend to anyone (all within 14 months).
I'm an experienced single traveller and have gone totally solo numerous times (arranged own hotels, flights, etc) but although more expensive its far more fun on a group holiday and I've made many friends I keep in contact with.
I'm not single at present but I'm still looking at doing a JY holiday because my partner struugles for time off work and knows I'll go mad if I don't holiday, (travel addict) lol.
It really is a great way to travel with other like minded people I'm sure you wont be dissapointed.
Mick