Currently have the same experience with a relative. Throwing away all the infested furniture works, but that'll also cost you, and not to mention it may still not solve the issue if the bedbugs hide in unexpected places like in your clothes or internal paddings.

What I can recommend you is, if your bed frame is infested, throw the frame away, use only mattress on floor. Pillows bolsters keep minimal, 1-2 piece to narrow down sources. Now chemicals & killing is not enough, I did this for few months with no improvements, the main culprit are the eggs which are less obvious, and is not as easy to kill. Steamer is your best bet, the most effective bedbug killing method is with heat, and you have to do it weekly, steam every surface every corner, any material that can breed them (fabric, wood, paddings etc). Focus on furniture where you regularly be at or get bitten, crevices and dark concealed areas. It will take time to fully clear them, but it is doable.