http://www.mangago.me/read-manga/sakura_gari/an/sakura-gari-chapter-9.html/90/ it's said...

so i believe he lived .. just like the sakura tree, even efter being cut .. it lived on
so both souma and masataka now can live together with nothing to hide, cause both of them have being through so many difficult

I hope so too... Souma live such a harsh life.... isn't it about his turn to start gaining happiness. It can't be the end for him..

I completely agree with anonymous!
In the story, the sakura tree has a symbolic value. Souma, as a child, took all his anger on it, all his desire of self-flagellation were transposed to it (hence the scars and cuts left on it). As someone who was helplessly abused, he could not help it but sink into despair which turned into self-hatred and the latter into self-destruction. All the loveless liaisons he had with all these men and women fall into that, an attempt to destroy himself. He already felt rotten as a child (children when abused usually tend to blame themselves for what is happening to them "I must be a rotten child because no one loves me").
This sentiment aggravated because of his role in the murder of his step-mother, and starting from that day onward, Souma felt even more corrupt, more rotten but yet unable to break free from this vicious cycle. He couldn't even take his own life to alleviate his soul and heart from the burdens and feeling of guilt he is carrying.
The Sakura tree in the garden, which served as a shelter and an inanimate witness of his suffering in his childhood, reflects the fluctuations of his state of mind and that of fate.
Though he initially wanted to destroy it, he realized that the tree only carried on to blossom even more vigorously throughout the years. He has pointed out to this just after being accepted by Masataka. It means that even damaged souls and lives like his can still find salvation. He found it in Masataka's love who granted him his unconditional forgiveness.
Of course, he thought that he shouldn't run away (or hide anymore) and that his crimes shouldn't remain unpunished, that is why he decided to cut ties with him. I don't think that this was the end though because the wounded Souma promised to live as Masataka wished for him to do so; and what did we see at the end? We saw a hopeful Souma under the blossoming reinvigorated tree which symbolizes the hope he found in Masataka's love and acceptance (actually they have both accepted each other, Masataka is no longer a "dirty child" but a loved child who realized that no one could ever love him as much as this man does).
Finally I would like to point out that the story is narrated from Masataka's point of view.
Chapter 9, p. 48 he says: "AT THAT TIME, I clearly understood this much"
This sentence means a lot, it means that he is narrating his past from some point in the future. So we can refer to it in order to determine whether Souma's wound was fatal or not (if it was, Masataka's narration and tone would have been completely different).
If we add to this the sentence from page 50 (" [...] no matter how deep, or intense, the only one who would love me this much would probably be this person, for life") and the view of the falling petals from the sakura tree and the ray of light at the end, it would be fair to say that this is the proof of an ever-lasting bond between the two. I don't think that Souma will ever give up on Masataka. As long as he breathes, he'll continue longing for him. The faithful Masataka will never hesitate to go back to his side too ... perhaps we can trust them to be reunited again as the sakura tree carries hope and the promise of an ever-lasting love to them ... and to us too.