Hi, Since your child is one and a half years old, her food and nutritional requirement would have not been possible even if you had been having enough milk. Yes, feeding her off and on, or during night, not primarily to feed her but because kids are used to of latching and it is hard for them to wean is fine. I think you need to feed her properly before you put her to bed. After her meal, after a while, you can even make her drink milk. Only that, if the baby sleeps after having milk then you will have to make sure that you get up at night to make her pee, if you are reinforcing the habit of peeing in the toilet. I think she is not eating properly or must be having her meal way too early and which is why she feels hungry at night. I think the best is let her have her dinner around 9 and then at around 10, make her drink milk. Or plus minus the timings according to her sleeping schedule. Then even if she will latch on to you, it will be just to get the feeling of being latched and not out of hunger. Sometimes, babies internal clock is set to wake up at the same time as they do everyday. And at times, they wake up because of Startle Reflex, where the baby suddenly moves or stretches his arms or legs. This happens for just a few seconds but it wakes the baby up. And sometimes it also happens because if you say feed your baby in the afternoon four times or after 3 hours of interval then the same pattern is followed by the baby during the night. All, I suggest for now is try feeding your baby well and feed her milk before she is about to sleep. This will keep her full throughout the night and she would sleep well. If this doesn't work, please see her paediatrician and take his advice.
I think, you can keep a kettle with warm milk in it beforehand before going to bed and whenever she wakes out of hunger you can put it in the bottle and feed her. Also, making her go to bed with full stomach will also make her sleep in peace. Perhaps, she is not eating fully and that is why waking because of hunger. I suggest feed her well before going to bed, as if the kid eats well then they do not wake up and sleep peacefully. She is one and a half, you can by all means feed her solids, vegetables, pulses etc.
i'll suggest you try increasing her dinner portion a bit more, maybe she is actually hungry and waking up because of that, more than the comfort factor. you can keep a sippy cup ready to give her at night, but try to avoid that as much as possible. if she is full at bedtime, she will soon give up on the night feed. if required, give her a cup of milk right before she is about to sleep.