I really feel for you! My twins (now 5 months) did this only from 5pm - 10pm for 10 weeks and it took me to breaking point (along with their silent reflux which is only just being sorted).
Try a stretchy wrap-type sling like a Moby. There are facebook groups where you can buy a Preloved one. I have a Moby and a Hana baby wrap. A tad tricky at first but a life saver. Your LO might even prefer this to buggy when out and about. "Babywearing FSOT" and "affordable slings for swap and sale." People there will advise on type of sling and how to position baby. Have you got a local sling meet?
Have you tried different dummies? Some are harder for them to use.
You will bond! at times I honestly felt having the babies was the worst thing to have ever happened to me and felt so crushingly sad that I had done this to my DP and I. This did not last. I am now a very happy mum with two very lovely babies. (They still have their moments, mind!) It'll pass. LO won't do this forever, no way. It's so hard in the fug of the early days to accept that anything will ever improve but it does!
Is she opening her bowels frequently? Gaviscon made mine so constipated that the reflux was preferable.
Demand a referal to a paediatrician- we are now on better meds for reflux and life is easier. (Mine began a nursing strike at wk 15 - feed aversion due to silent reflux. Now much better).
Music sounds like a great idea.
Could you swaddle LO and use white noise to soothe? Google fourth trimester too as you might read some things that help you out.
Finally, you're an amazing mum. the fact you are so concerned for LO shows that - yes, it's very tough, but you do love your baby and there will be a time when this is a distant memory.
and
for you.
Ps. Online shopping is your friend! Lots do introductory offers too.