If you can repay the aid in some way, such as by helping with another task, then you've bettered both of your lives. If you keep seeking help over and over with no reciprocation, you burn bridges and become a burden. Among honorable, mature people, gift begets gift. I share my meals with my partner at work; in turn he shares with me the next day, or buys me a coffee when we go to visit his wife at lunch time.
It's important to differentiate between 'hospitality' and 'charity'. I believe the Norse myth lays the rules out well. Hospitality is given to people who are friends, or at least not enemies (potential friends). It helps someone to get back on their feet and enable them, or perhaps lets a weary individual rest and recuperate. The period of hospitality is traditionally said to be three days (see the Lay of Rig, and/or Grimnismal). It's productive and is not a burden, and if needed -at least in this circle- is reasonably expected.
Charity is much longer, past the time when one has worn out their welcome. In Charity, one party is sucked of time, energy, and resources. More often than not, the receiving party is only crippled further by this act, and dependent upon it. It is non-constructive and kills the spirit. A good example of this comes from my childhood, when my mother allowed an old friend and her 18 year old pot head son to move in to our house and stay with us. They trashed the place routinely, lived in filth, smoked in their rooms, and were consistently unemployed. They bred spite and misery, and nothing more, while receiving our charity.
Hopefully that made sense. This is obviously only one view on the subject, but I hope it's given you a different perspective to look at and consider.