The Crowdfunding fundraiser was set up to raise money to help in the search for the 42-year-old mother-of-four - and for others who find themselves in this situation.
Helena was last seen close to the Foyle Bridge on November 24, 2019.
There has been extensive ground and water searches taking place to help locate her.
"At the time of writing this Helena will have been missing for 3 weeks, there are a range of charitable rescue teams and members of the public involved in the search and we are raising funds to aid in the daily search for Helena until she is found," according to the appeal.
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"Helena is a much loved wife and mummy of 4, she is deeply missed by her family, friends, the entire communities of Desertmartin, Draperstown and further afield."
It adds that "currently there are 2 searches daily on foot on the river banks led by rescue teams during low and high tide, along with water support from a range of different organisations".
Updates on how you can get involved in the search or for updates on how the search is progressing can be found on our Facebook Page https://www.facebook.com/BringHelenaHome/The post adds: "Many thanks in advance for your support and with this source of funding we will be able to provide more aid and help to everyone involved in this and future search's for other families who find themselves in this situation."