There is a Minhag to say Parshas Hama'an as a segulah for parnassa, on the Tuesday of Parshas Bishalach. By saying this parsha, we recognize how Hashem gives us everything we need, and we thereby open the channels of Emunah and blessing into our lives.
What can we learn from this parsha in regards to our struggle?
When some of the Yidden in the desert left the maan overnight - against the will of Hashem, it rotted. "Do not leave it over until morning", Hashem commanded us. Hashem takes care of our needs "one day at a time". We never need worry, "what will be tomorrow?".
Also, as much as the people gathered, they found that they had gathered exactly as much as they needed for their family. This teaches us that as much Hishtadlus as we think we are doing, we will get exactly what Hashem intends for us to get. This mindset is so critical in dealing with addictions. When we try to "take care of our own needs" we are essentially saying that "Hashem is not supplying what I need, so I need to take it myself". This is the biggest lie. What we take for ourselves against His will, will end up rotting; we will have nothing from it. And we will lose in other places in our lives. Conversely, the pain we feel when giving up pleasures we "think we need", will save us much pain in other areas of our lives. And we will get pleasure from other places; real pleasure; pleasure that G-d wants us to have.
At the end of the day, Hashem takes care of all our needs. We need to learn to "let go and let G-d". As the Pesukim in Tehhilim say: "Throw on Hashem your burdens, and He will sustain you"... "Roll on Hashem your ways, trust in Him and he will do....