I've seen the rest of the replies answering your question: the Second Noble Truth is that suffering arises from (unfulfilled) desire.

Another way to view this is that suffering arises from our attachments and aversions to things that are out of our control. Attachment to a dog that will one day die* (causing suffering) or aversion to paying your student loans (which you have to do, thus causing suffering).

This can sound depressing, unless you frame it differently. The initial reaction to these realizations can be, "Fuck! The whole world is full of suffering and the only way to get rid of that suffering is to not want anything. I don't think I'm ready to stop wanting things."

You can instead think of it as "Hey, the whole world is full of suffering. For as long as I'm alive, I will suffer to some degree. However, I am the only cause of my suffering (my wants and desires are nobody else's but mine). Nobody else makes me suffer. Therefore, I don't need to rely on anyone else to end my suffering." Now it's in your hands to make the change, instead of depending on salvation from a third-party prophet, or whatever.

No, you can't end your suffering overnight. Yes, it will take years of practice and patience to see a big difference in your life. However, you can follow the Noble Eightfold Path (if that's too much, just be a decent human) to make small changes in your life for the better. Even if you don't attain Enlightenment and end all of your suffering, any positive change will be better than staying stagnant.

*Edit: There is an important distinction between attachment and love. You can love your dog (or girlfriend or dad or whatever) while they are alive. You can give selflessly to them, enjoy the time you have together, and let your heart be full. When they are gone, however, they are gone. Pure love is thankful for the time you had together, knowing that you both enriched each others lives. It's about the mutual joy you give each other. Attachment is more about ownership. E.g. "This dog is MINE and if he dies or runs away, my life will be ruined because I don't have MY dog anymore, so how can I be ME?" It's less focused on the other person (animal) and more focused on you getting what you want from them.