Fateh's obsession with Jasmine is not over yet. He will very soon go back to mooning over her. Already Jasmine has realised her mistake as per the promo. She will try to make amends with Fateh despite him now being her Jijaji. She will do some silly stupid stuff and Fateh will forgive her. Jasmine has the habit of taking Tejo's stuff, this will be no different. Jasmine will try to take Tejo's husband and she will quietly watch or allow that to happen because she loves Jasmine. In the background Tejo will develop feelings for Fateh while he will consider her as a friend and help her overcome the hurdles created by his mum and siblings. In parallel, we will see Fateh and Jasmine reuniting (as evidenced by them exchanging garlands in the current montage during promos) and Tejo turning a blind eye (indirectly helping or supporting those two) as per current montage aired during promos. However, the only silver lining is that Fateh will not be able to carry through his plan of reuniting with Jasmine fully because of Tejo.
This marriage is no way the starting of Tejo and Fateh's love story. That is a long way off. We will be forced to see Jasmine and Fateh Romance even now. This marriage will result in the love triangle where Tejo will fall for Fateh while he still moons over Jasmine (as per prediction by the Astrologer in mall. Fateh's love line is strong but divided between two lovers one).
Fateh and Tejo'a relationship will take a lot of time develop and will be like a slow burn, simmering under the surface and quite subtle.