In 1997, Husen joined the Alliance 90/The Greens (GAL) party.[2][3] She was speaker of the party's youth organisation, Green Youth, from 1998 to 2000.[1][2][5] She acted as a member of the party board of the Green Party in Hamburg between 2001 and 2002.[4] Elected to the federal party board in 2002,[6] she served as its speaker in matters of women (frauenpolitische Sprecherin) until 2006.[7][2] In 2004 she was re-elected as a member of the federal party board over Anja Hajduk, the then provincial chair of the Hamburg branch of the Green Party and member of the Bundestag (German Parliament).[3]
She served in the Hamburg Parliament from 2004 to 2008.[2][8] She was speaker for health politics of the GAL fraction, and a member of the budget committee, the health committee and the committee of consumer protection, and a substitute member of the science committee. She represented her parliamentary group in sub-committees for information and communication technology and administrative modernisation as well as for public service and human resources.[2] She was not elected for the following term.[9] In 2013 she was a candidate for the Bundestag representing Hamburg Wandsbek, but was not elected.[9] In May 2019, when a new black-green coalition [de] took office in the borough diet of Eimsbüttel, it was suggested that she be elected as the borough's municipal councillor (Bezirksamtsleiter [de]) in replacement for a politician of the Social Democratic Party (SPD).[10] She collected only 25 votes, one short of the necessary 26 votes.[5][11]
Husen suffered head injuries from a fall off her bicycle in Bayrischzell, Bavaria, on 26 June 2022, while participating with her partner[13] in the 29th Rosenheimer Radmarathon.[12] She died from her injuries on 28 June at a hospital.[7][12][14] She was 46 years old.[7]