Low milk supply

My LO is 5.5 months now and for a couple of months now he hasn’t been gaining weight and he’s been fussier than normal and sleeping less even though he’s tired

His doctor told me that my milk is no longer enough for him to grow (EBF so far)

I tried everything to get my milk supply back up, power pumping, supplements, energy drinks .. everything and nothing seems to work

I’m so frustrated and sad. I’m angry at myself for not being able to give him enough food

I have to give formula now and I’m afraid I’ll lose the bond I have with my LO when he stops taking the breast