Beanie, please don't think that. You're totally sleep deprived and at the end of your tether so don't think about anything like that. By asking for help you're already a wonderful mum!
Is Emma ebf? How much food is she having during the day on top of feeds? What medication is she on for reflux? Also, does she sleep in her own room or is her cot still in with you?
I had a nightmare time with my son and sleeping, but he has behavioural difficulties and at nearly 8 still doesn't sleep before 11pm at night (that's a good night). When he was younger I didn't know this though and we massively struggled with him. At 7 months he refused to go to sleep on his own, he had to be sleeping on one of us then would get up hourly at night. We tried everything and he refused. I was so against controlled crying but eventually I used a method that's softer and only for over 6 month olds. After 3 nights of using it he self settled at night and slept a solid 6/7 hours then would wake and go back to sleep. I would do it again in a heartbeat. I'm not advocating CC but this other method was a life saver for me. If Emma has nights she sleeps better then you know she's capable of doing it so may be worth looking into some methods you may find suits you as a family? Our sleeping issues obviously came back but as it's behavioural we know it'll always be an issue. We've been involved with sleep Scotland too, as at 14 months our son could climb out his cot
creating whole new issues. We were advised to do back to bed routine with him and keep a diary of progress. On his first night he got up 77 times!!!! But we persevered and by night 7 he didn't get out his bed at all. I feel like a master with sleep issues, they've plagued me my whole motherhood
There is an end in this for you hun, I think the fact you're going back to work soon you're feeling more pressure to get on top of this. Sorry if I've repeated what others have said but if I can help at all, let me know. I hope you're okay, please don't beat yourself up xxx