It sounds like you are overwhelmed. The first month or two is hard for mothers of premie twins. What would make things much easier is to get to the point where you are just breastfeeding, no bottles and no pumping. Babies often don't nurse well when they are given bottles. That can explain the problems with latch and during feedings.
It's normal to nurse every 2 - 2.5 hours. Breastfed infants need to nurse 8-12 times a day. Right now it would be ideal if you were staying in bed with them most of the time so you can get breastfeeding established and recover from the birth.
Formula doesn't make life easier. You have stinky babies and stolls. Your clothes and the babies clothes along with sheets, blankets, ect. get stained. Statistically the babies get sicker more often. Premies are more of a risk for RSV. Breastfeeding is protective and if babies do get RSV they are less often hospitalized. It would be awful if one or both of your twins had to be in the ICU with RSV because you stopped nursing.
Breastfeeding has lifelong health consequences for you and your children. When your children are adults what would you say if they asked why you didn't breastfeed them. I hope I am motivating you. It's hard now but it will get easier. Try meditating for even 5-10 minutes a day, it can help when you are around crying babies. You could call La Leche League and they should have a list of Leaders that have breastfed twins. I hope things get better for you soon.
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