I think my experience was very similar to yours with my first. I was stuck in a vicious cycle of trying to breastfeed, bottle feeding, pumping, the lactation consultants gave me all sorts of (in retrospect) silly things to try. I was exhausted and not enjoying my baby at all.
At 6 weeks, finally decided that it was sink or swim time, she was either going to breastfeed or not, but I wasn't going to mess around with all the supplementation. I fed her constantly, like every hour during the day and throughout the night. It was only after I started this that I saw that "baby drunk" look (you know, where the baby is so stuffed with food that they get all relaxed and start to fall asleep.
At the next appointment, the lactation woefully commented that my baby had only gained half the weight she should have so I was going to have switch to formula. I said, nope, I started my breastfeeding boot camp halfway through so the fact that my baby gained half the weight she was supposed to meant that my method was working. I never went back and successfully breastfed her (and her 5 younger siblings).
That stuff they tell you about how you should nurse for 10 to 15 minutes on each side every 3 to 4 hours BS. You nurse that baby if she so much as looks at you. I learned that in the beginning, you might nurse for 5 minutes on one side every hour. The feeding every 3 to 4 hours is when they are older. If the baby is awake, you try to nurse her.
If you aren't dealing with medical/physical issues that are preventing the baby from nursing, I'll suggest simply spending a day holding the baby doing nothing but nursing and reading or other relaxing things (this is your first, right?). Nurse all the time and don't do anything else, just for a day and see how it goes. I got too hung up in thinking that I should still be able to do everything I normally do along with all the baby stuff. It doesn't work that way in the beginning.
And if this still doesn't work, please know that there is no harm or shame in using formula. I have zero tolerance for people who try to shame moms for using formula. I only breastfed because, at least for me, it was easier once I got it down. But I know other moms who could breastfeed and chose formula. And their kids are just as smart, beautiful and charming as mine.
As for the cost, it is a small price to pay for the baby to have a happy, healthy mom.
Good luck.