So basically you have long hair which you chemical treat, heat style and mechanically damage? Therein lies one part of the solution, too many different ways to abuse hair, stop or cut back on everything possible, find alternatives. Remember that even if you only flat iron or colour once a month that is twelve times a year or thirty six times for three year old hair (roughly eighteen inches long).
Unfortunately hair is dead so you cannot permanently repair damage, only patch repair it but some damaged hair is unsalvageable. The more damaged your hair is the drier and frizzier it is likely to be and the more effort and products (mostly conditioner!) are needed to get it looking and feeling healthier and under control. The long term solution is to stop damaging your hair, stop making excuses about time and events.
Many here are students or single moms holding down a job, many here are on a budget, many here have events to attend or need to look polished for work. It may be that you would do well to have a really good haircut to get rid of the worst of the damage and leave you with an amount of hair you can still easily put up and learn to make beautiful before growing more length if you wish.
Again try heat free methods of straightening like wet wrapping. Try not to ever brush your hair dry, try not to brush it period. use a wide tooth comb and section your hair to prep for straightening. Don't underestimate the effects of mechanical damage, you can do irreparable damage in just ONE rough session with the brush or a hot flat iron. The InStyler looks vicious, a rotating brush with high direct heat is two forms of damage in one little gadget. Up dos can be good protective styling OR damaging if you do them tight, the same style every day or the wrong tools to secure them.
You need to give us more information on your products and routine however basic it is, we can't help if you are vague and dismissive. Please tell us what products you are using at present, even if that is a couple of shampoos and conditioners and heat protectants in rotation.
I have been permanently dying my hair for way over half my life. IME colour safe shampoos are next to useless, some are actually harsher than regular shampoos. I currently use a high pigment semi permanent colour on the lengths, conditioner only wash in cool water, leave in conditioner containing ingredients beneficial to damaged or porous hair. My pink-red lasts two to four months and is still rich and bright, I only redye because of the root growth. With commercial box dyes, sulphate shampoos and silicone conditioners my red lengths were dull and washed out after six to eight weeks.
One of the first things you might do is a chelating shampoo or two to rid yourself of build up from hard water, swimming, silicone and polyquats in conditioners and styling products. Beneficial ingredients to use thereafter on porous or colour treated hair include coconut oil, hydrolysed protein, ceramides and panthenol.
If you are on a budget there are drugstore products you can use within the Curly Girl method, many also make their own deep conditioner. For example a cheap conditioner like Suave Naturals plus honey or sugar syrup plus aloe vera gel plus coconut or olive oil. You may have the ingredients already in your kitchen or bathroom. Many of us do our deep treatments (coconut oil plus honey) overnight on dry hair to save time.