Hey im just looking for some advice

My little baby girl is 15 1/2 weeks and we are not having a very good time right now
I only breastfed till about 8 weeks but then we had a bad few days and i decided to top her up with some formula....worst descision ever! our problems started from there, my supply dropped then she would fuss and fight at the boob coz i think she didnt like that it wasnt coming out as fast. she wouldnt suck long enough for the let down to happen....a tone of problems started! I have been seeing a Lac Consultant and shes been so helpful. She thinks that bub has reflux and that is contributing to her being so unsettled. we have started on losec its been 5 days so hopefully it will start working soon. back to the breastfeeding, im am taking domperidome and that has boosted my supply but she still fights as soon as the flow slows down and never really finishes a feed unless shes really sleepy. im still topping her up thru the day and i just dont know if its worth the stress. i really want to continue to breastfeed but i dont know wether shes just going to be happier with a bottle. shes putting on plenty of weight but shes just never ever happier for longer then half hour and never sleeps for longer then 1/2 hour during the day and at night she continues to wake all night....she used to sleep thru the night from 2 weeks up till about 8 weeks! was anybobys elses bub more settled when they started bottle feeding? i really need some help