Please dont compare Vaslaal with Gulsar. Both are different. The major difference is the former one is mutual love and the latter is something you call onesided love. As far as I know even though Vasanth loved Gulaal, she was not his priority. I mean he was ready to sacrifice/lose her for the sake of his villiagers and family. But Gulaal was/is madly in love with him, her love for him is of more intensity.
Kesar's love for Gulaal is something you cant express in words. Gulaal is needed for him even for his mere existance. Kesar loves Gulaal than Vasanth did. Just like Gulaal cannot accept anyone other than Vasant, it is impossible for Kesar to accept any one other than Gulaal(provided CVs dont bring any further twist).
After all true love happens only once in a lifetime.