That's amazing to hear, Vietnam and Cambodia are incredible destinations, the experience is out of this world! - Feeling a little apprehensive is totally understandable Linda and you will find that many people are in the same boat as you. I can assure you this feeling will quickly dissolve when you are met by your Riviera Tour Manager at London Heathrow. Plus, you will get to enjoy a welcome dinner on the first evening, which breaks the ice and enables you to mingle with your fellow travellers, should you wish.
Whilst you wait for other solo travellers to respond, why not check out our blog, there are a few articles on solo travel that I think you may find useful.https://www.rivieratravel.co.uk/blog/ca ... traveller/