Welcome Flower! I am a former yo-yo-er too. I think everyone is!
Only a small percentage of people actually maintain for over a year - so you have done great! But now you want to be that even smaller percentage of people that maintain even longer. You recognize the problem for you, sugar. Usually there is something else going on too - it's such a mental thing! Starting a diet, maintaining... I mean.... it is more mental than physical.
I've been maintaining just four months. I am feeling very strong because I am still in the honeymoon phase. This is the longest I have ever maintained. Actually in retrospect, I have never maintained. In the past I never reached goal, or the rare times I did reach goal, I thought that meant I could eat whatever I wanted. So this time, my goal is to maintain.
The support and advice here is great! Post your questions and the wise people will help you!