The 30-year-old mother of three was stabbed  before her house at Hazel View in the Lagmore estate was set on fire on Sunday.
Ms Dornan's mother, father and three young children followed her coffin into Christ the Redeemer Church in Lagmore.
Fr Martin Graham said the world was much poorer without her presence.
"Jennifer was a vibrant human being with a love of life and a joy and energy that attracted many friends," he said in his homily.
"She enjoyed life so much and she was the life and soul of any party. Jennifer knew what she meant to a great many people and she enjoyed company.
"She was quick and razor sharp in mind and in tongue. She gave everyone plenty to laugh and smile about and she never had to try hard.
"Her nature, her personality was one that even with her own troubles and worries she could still smile and help others to do the same.
"This world is the poorer now that Jennifer has left it, and with her buoyant personality it will also be so much quieter."
On Monday, police announced they were treating her death as murder.
They later released a picture of a knife like the one they believe was used to attack her.
The knife is almost 14 inches long and has distinctive orange and white markings.
A 39-year-old man who was arrested on Wednesday on suspicion of withholding information about the murder, has been released pending a report to the Public Prosecution Service.
Det Supt Kevin Geddes said detectives were "following a definite line of inquiry".
He added: "We are particularly interested in the movements and whereabouts of a man seen leaving Jennifer's home at 04:20 BST on Sunday.
"We believe he walked from Hazel View, through Lagmore to Poleglass. We believe he was wearing a grey T-shirt or sweat top and a light-coloured bomber jacket.
"At some stage, we believe he got rid of the grey top and light-coloured jacket and obtained a red and gold sports jersey."
West Belfast murder victim Jennifer Dornan has been described as a "vibrant human being with a love of life" by her parish priest.