Ketu-Rah starting from 20-02-2018 will create better chances as both these planets are in 1/7 axis (with Ketu having 2,7,11 in planet and nakshatra while Rahu having 7,11 in planet and 11 in sublord). Also Rah/Ket show sudden changes.
Purpose of Jyotish is to be transparent and as 4 malefics (Ketu, Rahu, Sat and Sun) are afflicting 7th house in Chalit, chances of happiness from marriage is slim.
Hope you find what you seek