Until you break off that relationship, you will continue to hurt yourself and those around you. The guilt you feel is useless unless you use it to motivate yourself to do better. Get yourself into detox and a long-term drug program. Don't get involved in any intimate relationships until you have been clean and sober for at least a year. Work off your guilt by getting involved in positive activities where you help others.
Happiness is a byproduct of doing the right thing.
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