Hopefully some pointers to help with your questions:
Women suffering diarrhoea (for all sorts of reasons) have fallen pregnant, because the hormones in teh 'pill' have not been absorbed, instead carried on through the digestive tract. Having said that, these cases tend to be prolonged diahorrea so there is a period of time without proper hormone uptake (see instruction leaflet for cautions).
The Liver Flush
(Dr. Hulda Clark
e method) induces diarrhoea fro one morning after that things settle down, so you might like to delay the usual morning 'pill' taking timing until midday or afternoon, if you want to be absolutely sure of protection, look to timing your Liver Flush
early or late in your menstrual cycle, and / or get your partner to wear a condom.
Depression: not good, and I sympathise, check out the book 'optimum nutrition for the mind' by patrick holford, this shows you how to build up your own serotonine levels, rather than take drugs to limit serotonine destruction. There are also nutrient combination supplements to support serotonine production which are well worth exploring.
As for vitamins and supplements, your best investment woould be in a Green Power juicing
machine, and committ for one month to two green juices a day made from fresh organic vegetables / salads, within a few days you will be feeling the transformation, by the end of the month you will be a different person, sure as sure can be.
Hope this helps