"She thanked me and told me she loved me but refused any help."
Dawson was under severe financial pressure after quitting the top-rating Australia's Next Top Model and reportedly borrowed $85,000 from friends.
He said given the tragic events that unfolded a few days later he wishes she had swallowed her pride and taken his money.
"Maybe it would have taken a lot of the burden off. No one would have ever known," he said.
The 43-year-old, who has dated a string of glamorous women, denied the pair had been lovers, saying sex would have ruined their friendship.
Ibrahim has been a well-known figure in Sydney since opening his first nightclub aged 18. His past featured in a 2010 television miniseries Underbelly: The Golden Mile.
On Friday, Ibrahim said Dawson's death still didn't make any sense to him and he felt her loss keenly.
He would have even employed her as his personal driver "just to keep her going".
A New South Wales' coroner is due to rule on the television star's death next month.
Meanwhile, an Australian current affairs show examining Dawson's descent into depression will kick-start a six-month charity fundraiser.
Sister Vicky Dawson said Channel 7's Sunday Night programme next week would highlight her sister's death as part of a wider investigation.
She and her sister Robin Barclay had been interviewed for the show. Australia's Next Top Model judge and close friend Alex Perry is also interviewed.
"The focus of the show is to help people with depression to try to stop people committing suicide," she said.
The piece would also launch a website devoted to fundraising and showcase Charlotte's foray into designing canvas cushions and coasters in collaboration with Billy Allen Homeware.
Vicky Dawson said profits from sales would go to five nominated Australian charities.
Where to get help
• Lifeline: 0800 543 354 (available 24/7)
• Suicide Crisis Helpline: 0508 828 865 (0508 TAUTOKO) (available 24/7)
• Youth services: (06) 3555 906
• Youthline: 0800 376 633
• Kidsline: 0800 543 754 (4pm to 6pm weekdays)
• Whatsup: 0800 942 8787 (noon to midnight)
• Depression helpline: 0800 111 757 (available 24/7)
• Rainbow Youth: (09) 376 4155
• CASPER Suicide Prevention
If it is an emergency and you feel like you or someone else is at risk, call 111.