i dun own a maltese but my family has a basset hound.... we spayed her.... the surgery was in the morning but by evening, we could bring her home already and just let the wound heal....
if there are other dogs in your house, do quarantine your dog as you wouldn't want other dogs to rip open the wound before it heals.... after the would heals, she is her usual self already....
also, many responsible dog owners would recommend you to spay/neuter your dogs regardless of breed to prevent unwanted pregnancy.... this surgery wouldn't change your dog's attitude towards you any bit....
benefits of spaying/neutering
1. females wouldn't come on heat, leaking blood and attracting males....
2. males wouldn't go bonkers when they smell a female on heat....
3. they stop marking teritories
4. some say their lifespan increases (but i'm not sure of this though)
5. males are less aggressive
hope this helps, cheers!