Not sure how I ended up here -bad search parameters- however, since I'm here, if you like tough love, read on:

You say that your sister had it good growing up, but I assume that you are talking about material wealth.

Actually, I'm going to stick my neck out here and say that I know that you are talking from a materialistic view point, and that you haven't considered what type of emotional support she received as a child, because certain facts about rearing children are as immutable as a ball always rolling down a slope.

Basically, all children raised without unconditional love, and unable to fulfill the set conditions to feel loved, will make bad life choices -like your sister. I would bet my soul, on the fact, that the only difference between you and your sister is that you accidentally fulfilled the conditions needed to feel loved by your parents, via genetics or sex or maybe by simply being born first or last.

How can I tell that the love you received wasn't unconditional either? Well, the way you talk about your family, and in particular your sister! I mean, you literally have a need to raise your own status, in your eyes, by comparing yourself with someone who is struggling so monumentally with life.

Seriously, emotionally your sister is a child, and if you need to compare your success against her, then you too must be, emotionally, a child.

If you seriously want to help her, then go and find her, and talk to her without pointing out all her weakness and flaws. She already knows that she's a piece of shit, her primary carers told her this, directly or indirectly since the day she could crawl, so you basically aren't helping at all: you are merely rubbing salt into her wounds.

So, why are you compelled to do this? To try to help by making things worse.

Because you are the exact opposite of her, and yet you are exactly the same.

If you understood unconditional love, you would never act superior to her, ever. You would never parade all your perceived strengths and attributes, that are the complete opposite of her perceived weaknesses, because you would know that in another time and place, with different parents, she would be the golden child, and you would be the piece of shit, and that knowledge, instilled from childhood, would have made you incapable of making adult decisions.

Deep down, you know that it was an accident that you fulfilled all the requisite conditions to feel loved by your primary carers, and that is why you need to be reminded, probably on a daily basis, that you are great, and when you need a real confidence booster, you find your sister, or write a post about her. If you truly understood that you deserve love, and are worthy of love, then you wouldn't do this!

So, if you truly want to heal your sister, go and ask for her forgiveness.