These issues are quite normal. The longer you have been in, and especially for those born in it, the more they have shredded your circle of friends outside the organization. They program train you to equate confidence with acceptance by those within the Tower ("Why should they seek friendship with this wicked world that's doomed anyway?"). They push doing ever more as a yardstick for worthiness, and anyone that breaks the rules or isn't doing "enough" is given those guilt trips and intentionally made to feel like "swine that has returned to rolling in the mud" and "dogs that have returned to the vomit".
This doesn't always go away in a few months. And this is especially so if one has family in the Tower (and they push and hound everyone to get their whole families in, so if one leaves, that one is going to have a harder time than if they had not joined). Those with families in are likely to have problems in this area for life, or until their whole family is out and not going back (whichever comes first).
And there are other areas that they entwine your life with the religion. Many work for other Witlesses in cleaning businesses. Others have landlords that are Witlesses. If one person messes up or quits the religion, that is going to affect their work situation as well. And with no education beyond the basics, they are going to have a miserable time trying to find another job. Many do go back to college, but catching up is still not always possible. Usually, in landlord or employer situations, the time between the disfellowshipping and the time that they have to leave the apartment/room or the job is usually extremely short, adding further to the hardship.
Problems with confidence associated with the religion are normal, also. They train people for one thing only: to be God machines that think of nothing but how effective they are at spreading the virus to others. And when they fall short, they find that success in other areas in life is not forthcoming because they have not been trained for it. This is worst in people that have been raised in it, and worst if the parents are strict in the religion. And it can persist for a person's whole life: the Tower wants it that way to get people who have messed up or left to return.
My advice is not to fall for their illusions, non sequitors, and guilt trips that they are probably using to get you back in. Going out and getting a college degree will help--even if you can't afford a whole degree, taking a few courses is better than nothing at all. Preferably, you will take courses that will help you get a better job. However, the main objective here is to get something you can measure yourself by other than the Watchtower Society's standards.
And one such yardstick is how much value you can create. This might seem tough, but every time you post something on this forum, you are helping to create something of value in keeping others from falling for the scam. Even the most trivial thing you create of value adds something. And if it's something you truly enjoy, you will have fun, create some value, and gain more confidence. No matter what, anything is better than what you had been doing--and better than what you would do if you ever went back to that puke.