So is dorian's romance worth doing? due to tresspesser epilouge

Yes. It is worth it. At least in my opinion.

It's one of my favourites, so yes, I'd say it's worth it. I didn't mind the Trespasser content, although I can see why some people disliked it.

The romance is utterly worth it. If you want the perfect "happy ever after" though, you should go with Josephine or Cullen or even for that matter, Sera. Note that all these are available to female characters and only one for a male. Apparently there are certain things the writer's don't think matter to male PCs.

I didn't feel Trespasser ruined the Dorian romance; apart from one rather tasteless "joke" on the part of the writers, which rebounds on several romances not just Dorian. I have romanced Dorian, Cassandra and Solas and believe me none of them felt good after the "joke". I found Dorian's romance the most satisfying and uplifting of the three. The problem with Trespasser is more with the epilogues and the fact that contrary to the assertion of the writers, they did not satisfactorily tie off the Inquisitor's story. Or more correctly, they tied off the "Inquisitor's" story but not that of your PC. Play it and see what I mean.

However, I disagree with the previous poster about the romance drawing out his confidence and bravery. You don't travel the length of Thedas to try and prevent a tragedy, utterly alone, if you do no have confidence and bravery. Try doing Champions of the Just, after visiting Redcliffe (so effectively rejecting him) instead of Hushed Whispers and you will see just how courageous Dorian can be when he is acting solely because he thinks it is the right thing to do. Whatever he decides to do back in his own country, he is equally inspired if you are just his friend, so it is not down to the romance.

The difference the romance makes in his life is that he now believes that it is possible for him to have personal happiness on an intimate level. That makes his subsequent decisions all the more poignant. As he says about the typical Tevinter psyche, he cares deeply about everything and ultimately that depth of commitment produces conflict in his direction in life. Dorian is a deeply passionate man and that is why I love him so. It is also why I find his relationship the most fulfilling and worth fighting for.

I only have one male play through in DAI and I created him for Dorian. I loved his romance, I thought it was so sweet. I adore his character to pieces, and even more so after playing a LI. There is so much to learn about a character after playing their romance, in my opinion, and if you at least partly enjoy Dorian's character then its worth doing at least once.

They do not break up in Trespasser. Dorian explicitly uses the word "love," you also have the option of saying it as well (in another scene), and also says, "There will always be an 'us'." The epilogue is written as if they are still together, and will be going forward.

Any player's feelings on the romance and the events in Trespasser are entirely subjective. I personally think that the entire romance is full of passion and deep feelings and have no issues with what happens in Trespasser. But that is for me and my Inquisitor. You may feel differently, as other players do. I don't think you can truly know until you play out the romance with the Inquisitor of your choice, which includes the roleplay aspects of having him reacting to the various scenes.

If you like the character outside of the romance, and are willing to make a male character to romance him, then give it a shot.

I don't know yet, still. My second try with him, but I don't feel that, what I felt with Anders or Fenris. I miss this feeling. (But still in progress, maybe will change...)