Jason plays for publicity. Bellarke is all publicity. I doubt he will do anything significant about them from now on... he will probably make Clarke kill Lexa, to use the same excuse as he did with Finn... "clarke is not ready for a relantionship, just to discover she likes to kiss girls"
And then put Bellarke in stand by for a whole season... that if they end up the season meeting up, which i doubt.