Weaning

Im pregnant with my second & have a 16month old who still breastfeeds. For the past 3 months she’s been wanting to be on the boob all day and all night. It’s much easier during the day because I can distract her but at night we co-sleep & all she does is toss and cries if I don’t stick my boob in her mouth. Her dad sleeps in the living room since he works and can’t keep waking up every hour or less! I really want to get her off, my back and shoulders are starting to hurt from laying sideways and my nipples are raw! Does anyone have any tips on night weaning? I need help!