Don't be so hard on yourself. Part of it is ageing too. As we age our estrogen goes down. Throw stress on top of that and the systems start to have problems. The copper in the IUD started to overwelm you. Keep in mind that you might have had more stress leaving your body less able to handle the copper. Stress slows down our systems and those systems are responsible for detoxing. So we fill up with toxins and that adds to more stress. The candida love copper and toxins. The more healing I do the more in control my candida is. 3 years ago I constantly had a yeast infection, now it's so much more under control.
I have been doing castor oil too. I don't think it's lightening anything but I do notice I have a bright glow in the morning after putting it on before bed.