Hun, look at the fantastic results you’ve achieved so far. You have gone from weighing 74kg to 63kgs. That is a huge achievement and you should be very proud of yourself for achieving such a significant weight loss.
I know it's hard to ignore negative comments, but you have to hunny otherwise they will fuel your negative self talk and as a result you will sink lower and feel more depressed and find it much more harder to continue with your fantastic success.
Next time one of your family members makes a negative comment, state clearly, with conviction in your voice that their comment has hurt you. You do not appreciate such comments, and if they want to say something negative to you, tell them that you're not interested in hearing it, because you are working damn hard to get to where you want to be and you've achieved great success. Ask them how they would feel each time they received a negative comment. Hopefully that should stop your family hassling you about your weight. Also, it has nothing to do with them so they shouldn't be commenting anyway, it's your body, you're an autonomous being making your own decisions it's not up to them, so tell them to butt out.
As to your boyfriend, you have your insecurities about your body shape but I promise you this, even though your boyfriend playfully called you 'big bum' I don't believe he meant it. He said it in a playful manner and did not come out of the blue saying 'you have a big bum'; even though it might have sounded as a criticism, it wasn't. My boyfriend calls my breast (now I have huge insecurities about them) as he's pillows: big and soft. The first time I heard this I thought he was repulsed by them and I felt very uncomfortable. So I had this very talk with my boyfriend, and he told me that men don't look at women the way women look at women, i.e. body part by part. They look at the whole package. You boyfriend is attracted to you the whole you, not just the body. Why would he be with you otherwise?
Ok so I'm going to read between the lines here and I do apologise if I have it wrong. I get the impression that you feel like he's with you for the sake of being with you, that he is using you for whatever he can get out of the relationship. If you are thinking this, stop. Guys are very unpredictable creatures, but they don't like being in a situation which is forced upon them. He is with you because he genuinely likes you, wants to spend time with you and wants to be with you. If he didn't feel those things he wouldn't be with you. They are either into you or they are not.
Yes we are bombarded with images of waif thin models every single day; pressure is being added to us women to be a certain size. It's in ads targeting women; it's in women's magazines. But men don't find waif thin women attractive. If you look at men's magazines like Ralph and Sports Illustrated you will see normal sized models, yes they are beautiful but they have touch ups too. If only everyone had airbrushing...but there is no such thing as perfect.
So remember you are not inadequate. You’re a very special person and you also have someone who cares a great deal about you and wants to be with you. Don't play the "if only" game, that leads you nowhere. You are already heading down the road you want to travel and you've already achieved so much. You will get to your goal weight.
GW1 - 70kgs
GW2 - 67kgs
GW3 - 60kgs