How does the ghost of christmas past act towards scrooge?

The past ghost is a reminder of what once was. Scrooge, after being shown numerous events of past Christmas', shouts "No more!" and tries to put out the Ghost's light by covering the ghost; Scrooge wants to extinguish the Ghost.

While on their trips, you can see that the Ghost cares for Scrooge since the Ghost notices Scrooge trembling and crying from visiting past memories. Scrooge is reminded from these events that he would spend his past holidays alone, which is what made him sob out in the first place (well it depends on which version of Christmas Carol you're listening too).

The Ghost has good intentions, despite the Ghost's bright light bothering Scrooge.

(Again, the answer varies on which version you're reading but this one's pretty generalized. Sorry if it's confusing or it's not the best)

The Ghost of Christmas Past is the first spirit to visit Scrooge after the ghost of Marley. It arrives as the clock chimes one. It is an ephemeral spirit that appears to be both old and young at the same time with light streaming from the top of its head. It takes Scrooge to scenes from his own past, showing him visions of his own childhood, of his young adulthood and of happier times. The final scene he presents is one that Scrooge cannot bear to witness: his lost love, Belle, with her family. Scrooge turns on the ghost and demands to be shown no more. He attempts to extinguish the ghost's light with its own cap, wrestling it to the ground. However, the light that shines from the ghost cannot be put out.