It's Time To Face The Truth.

OMG, Tiana,while reading I feel your pain, I had a friend go through the same, I'm here for you Tiara

eat real food. Since you use Kg you are lucky you live outside the US where we have GMO and if a person here is 5' they weight 100 kg and LOOK thin!

So maybe time to take off the limits and get off the scale
Go for a walk and then eat a huge steak with lots of fat
eat cream
eat butter eat bacon
eat vegetables like peppers, broccoli (I hate this cooked but love it raw) onions, garlic
Stop driving and walk
Once a week run like there is a lion chasing you (if you run for more than 3 minutes you are not running fast enough)
run until your legs muscles stop working properly
half way between the Lion run, lift something heavy
I mean like heavier than you are do this 3 times
if you can lift it 4 times, lift something heavier!

Forget what you look liker and go for how you feel.

It's normal to have no motivation to exercise and eat healthy, especially if it's not normal for you or part of your routine. I mean, once you get going it probably becomes easier, but the hard part is GETTING going in the first place. Not so easy to do and I have my own failed attempts to back me up on that. However, I want you to find whatever motivation you need to get going and stick with it. I hope that you attain whatever it is that you want from yourself and your body to feel comfortable and wear whatever you want. :)

You could try drinking some protein shakes throughout your day...i actually use them as a meal replacement, usually in the morning for breakfast before work or school because i'm lazy and it's a quick and easy way to shut my stomach up. But you can use them in between meals, the ones i drink taste like chocolate milk, they're called Ensure protein shakes. If you like chocolate milk it's an easy way to add some calories, protein, some fat and lots of vitamins... i think it's a healthy way to add some weight. And i feel for you, i had a friend who was underweight for years, it always made her uncomfortable because she felt like she didn't have a shape. She was very pretty though, and i can tell you are too, so i wouldn't worry about it too much! But if you really want to, I think you can make a change if you commit to it! I would think it would really only take a couple months, just find some things you enjoy that are packed with calories, and healthy fats, avacado, nuts, fish, eggs, etc.

Eat more. Like my mum used to tell me.

follow a good controlled diet,eat in time,drink good amount of water,do some good excercises and good sleep.It will certainly make you look in good shape.