DO NOT MARRY HIM! Once you marry him, you will become legally responsible for every debt he takes on. He has not demonstrated in any way that he is capable of managing his finances responsibly or that he loves you enough to sacrifice his immediate wants for your future together.
Put the wedding on hold, but do NOT give him your half of what you have saved to bail him out. Bailing someone out financially is fine when they are a reasonably responsible person who simply fell on hard times. That’s not your fiancé. He is someone who makes irresponsible decisions and then lies to you about them, repeatedly. Any money you give him to help him out will be squandered just like all his money before it.
Personally, I would just leave, as he doesn’t seem willing to put in the work to change anything. But at the very least, tell him that the wedding is off until he has his finances under control. And during that time, don’t bail him out financially, don’t take on the work of teaching him how to make a budget, don’t nag him to get the second job he needs to get. You can’t do this for him. He needs to take responsbility for his life and his finances because if he doesn’t, how can you ever trust him to be able to take care of a house, or children, or YOU if an emergency happens? You can’t. Protect yourself, because he doesn’t seem to have any interest in protecting you.