The incredible courage of the 24-year-old typified the spirit of this year's Great South Run.
Miss Forbes took more than four hours to complete the 10-mile run with her stepfather Eiffie Verboort and friend Dean Reynolds helping her every step of the way.
But sheer determination kept her going to raise money for children with leukemia.
And her spirit was matched by more than 12,000 runners who completed the challenge despite howling winds, rain and transport problems.
Miss Forbes had both legs amputated after being struck down by meningitis when she was 17. She woke from a coma after six months, during which time she'd had a massive brain haemorrhage and a stroke.
In June 2004 she started to learn to walk again, after her stepfather and mentor Effie Verboort hid her wheelchair.
Miss Forbes, from Crawley, West Sussex, who has adopted the motto 'who dares wins', said: 'I will keep doing these races.'
David Hart, from race organisers Nova International, said: 'There are so many inspirational stories that come out of the event but none more so than Clare and what she did yesterday. I saw her just as she crossed the finish line and she was still smiling.
'The last two miles had the wind and rain against her and I cannot begin to imagine how challenging it would have been for her.
'Her determination sums up what the spirit of the race is all about.'
The constant drizzle and grey skies didn't dampen the spirits of the runners or an estimated 18,000 spectators, who clutched umbrellas and huddled in raincoats as they lined Southsea's streets.
It is expected this year will have seen a record number of people crossing the finish line with about £2m raised for charity.
Lord Mayor Mike Blake, who was the official race starter, said: 'The weather affected many things and I think made it difficult for the competitors, but everywhere you looked you saw incredible good humour and great enthusiasm.
'The race has become part of the fabric of the city and the fact that the spectators were out there despite the weather show what kind of people we have in Portsmouth.'


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