[Marmeladov:] "I drink so that I may suffer twice as much!" (1.2.21)
Marmeladov is caught in a vicious cycle of suffering and alcoholism. He drinks because he suffers. The drinking pushes his family further into poverty. This makes him feel guilty, so he drinks more and wallows in his suffering. You can see where we are going with this.
[Marmeladov:] And here I, her own father, here I took thirty copecks of that money for a drink! And I am drinking it! And I have already drunk it!" (1.2.31)
Marmeladov asked Sonia for money to go drinking with. Money she earned by selling her body. He knows that this kind of behavior is low, but he also knows he won't stop. It's a testament to Raskolnikov's compassion that he's so nice to the guy.
[Marmeladov:] "[…] but Katerina Ivanovna, my spouse, is a person of education and an officer's daughter." (1.2.18)
The narrator tells us later that Katerina's education is what allows her to maintain a certain "dignity" and pride through all of her trials and tribulations. The suggestion is that education has value beyond helping one get that dream job. It can also be a source of sustenance. We don't know if Katerina is the best character to demonstrate that point.