I have no problem in straightening my hair its just the last couple of inches that look fluffy - not smooth. I use products and am currently trying Charles Worthington serum but it's not working. I also spray on Lee Stafford dehumidifying stuff; this works a treat for everywhere else other than the darn end bits! Forever hopeful..
Since having children, my once straight hair is frizzy and fluffy at the ends underneath (I have long-ish hair). I have tried frizz-ease, straighteners all to no avail. My hairdresser asked me if I wore alot of necklaces as my hair is wrecked at the back. I don't. She says I need to have alot cut off. Maybe that's what you need too?