I have naturally straight hair, but they are kinda frezzy, with a lot of volume mostly at the bottom. It's weird... They look damaged too, when I don't use heat, I don't have split ends and they look rough and get tangled a lot. Only when I brush them they look a little bit better. But the moment I go out they get tanlged again... But overall my hair is straight (like they don't curl or wave)... Help!!! I want them to be silky without having to use an iron, because even with that they will get tangled and rough looking when I'll leave the house :(
Try using those coconut oil hair masks once a week, which should help hydrate your hair and result in it looking and feeling silkier. I have heard that having cotton pillowcases also dries out hair, leaving it frizzy so perhaps try trading in cotton pillowcases for silk ones if you've already got cotton. As for your hair getting tangled a lot, using conditioner for dry, flat hair everyday should also over time help.
Get a haircut and use a good conditioner (like Aussie) and put some Moroccan oil on the ends of your hair. And stop using a straightener, that will only damage your hair even more. Damaged hair isn't always just split ends, dry and brittle hair is damaged as well. But if you insist on using a straightener, don't use a high heat setting and put heat protection spray in your hair as well.