Hi Nikki, and welcome to the forums
I'm sorry you're feeling so depressed at the moment, especially when you've done SO well to lose 25kgs. I know you might not feel this way, but you really should be proud of yourself as it's a huge achievement!
It can be really frustrating when you hit a plateau and you work so hard and lose nothing. I'm not really sure what I can suggest to you, because you seem to be eating well and exercising, which is usually enough to get the weight coming off again. Perhaps you could consider going to see a dietician to see if they can look at your diet, and make any suggestions? I know you monitor things yourself, but maybe it would be worth seeing someone else for an objective point of view? Same with your exercise, maybe you could book a session or two with a personal trainer, and see if they have any suggestions?
Try not to give up, you've come so far already, and I'm sure you will just feel worse if you let yourself slip and undo all of the hard work you've put in so far. You CAN do this, and you're worth it!
Let me know if you need anything