You stop gambling – is the easy answer. Easier said than done. I take it you have read around the site and know that you need to ban yourself from places where you might gamble. You need to curtail your use of money to gamble with (pass the responsibility of your finances onto your fiance – does she know about your gambling?) And you need to get support, not just from here but from your local area – a self-help group such as GA and / or counselling via your GP or (if you are in the UK) Gamcare.
I know from experience that none of this is easy – and for me there were a lot of slips along the way. I tried to put as much effort into my recovery as I did into my gambling and eventually it worked. It will work for you too – if you work it.
So that’s the practical advice. Talk to people on here via groups and get as much advice as you can and work on what will work for you. I wish you well.