Helen I'm so glad you're back! Forget the gain - you are back on the wagon now, and that's what counts! Are you still going to the clinic? They should be able to give you advice on what to eat..
Otherwise, maybe a dietician? I went to a dietician a couple of times when I first started losing weight (way back when - 140kg and NO idea what was healthy or not) and it was so useful - things like calcium, iron are so important to your diet and maintaining a healthy weight, and a dietician is often the best one to help you sort these things out. If you have health insurance, you shouldn't have to pay very much for the dietician - or if you go via your GP, some of them even bulk bill for certain patients.
If you would rather do it on your own for now, then my advice is (as somebody else said) to go to CalorieKing - this has helped me tremendously because it keeps you accountable! If you fill out the sign up thing, it will tell you how many calories to aim for.
In terms of exercise, cardio is very important for weight loss and heart health but weights will help you lose even more weight, maintain it, get stronger, and get stronger bones. I actually think you really need to do both, right from the start - as best you can. You were going to a gym for a while - can you get back into that and see a PT? I'd recommend you increase your incidental exercise as much as you can (I'm banning myself from the lifts at work), and try to get some cardio in 2-3 times a week, and try to do weights 1-2 times a week. I know you have a crazy schedule, but do what you can! Even if you have little hand weights and you lift them at work in your lunch break or something!
You can do this Helen - you are a strong woman, and don't look at the weight that has just crept back - look at the total amount of what you have lost - still an amazing effort! You can do this again. The most important thing is to keep going - jump back on the wagon and try again. You will get there in the end. You are already so much healthier than when you started this whole thing.
I know you didn't want cheerleading so I'll stop now. I've only just started posting again and I'm so glad you're back - I could do with your awesome support and motivation too
We can do this together, yeah? Go us!