The thing about Morrigan though was that you knew why she left. Also if you gave into her idea about the OGB then she left on considerably better terms than if you didn't. You were also able to vow to hunt her down (having only grudgingly given consent) or wish her well (because she just saved my boyfriend for me - because I always guessed he would take the dive for me). What was also good was when discussing my Warden with Morrigan, who didn't agree to the OGB (Loghain took the fall), she mentioned how they hadn't parted on the best of terms which she regretted. Now I assume she probably says that about every Warden who didn't agree whether they parted on good terms or not (though I suppose it could vary if the Warden did hunt her down and stabbed her), but my Warden certainly bore her no ill will, simply hadn't agreed with her plan, so I was happy she acknowledged she could have dealt with that better.
The Vallaslin thing feels a lot less romantic to me since PW revealed that Solas only does it to cover his A** because he got cold feet about revealing the truth and came up with the Vallaslin on the fly. I just find it a bit hard now thinking that my male Lavellan is going to be spending the rest of his days with "I'm a slave" written across his forehead. I've yet to play through the game with him but if Cory does mention it, then naturally he is going to wonder about the fact that Solas had no Vallaslin, yet is clearly not a city elf, and whether he knew. Anyway, leaving that aside, he'll likely be looking to Solas as a sort of mentor/friend who he respects and thinks Solas respects him and then suddenly he's gone. The odd thing is at the beginning you can say to him, what about when all this is over and his answer is that he hopes that people, like Cassandra, will remember who helped, which sort of implies that he'll stick around.
I think the problem is that I'm constantly manic depressive over Solas. I'm playing through again and smiling at all the instances that I so love about him but feeling deflated the next moment because now I know it won't last and somehow the epilogue makes a sort of discordant note in everything. Even before the game came out I never really believed that cover story about him being a simple apostate who lay around in ruins; I was certain he was going to be an ancient elf. So his reluctance to get romantically involved was understandable, particularly when you think how much older he is than Lavellan. May be he did feel he was taking advantage. And revealing something like that would be difficult enough without the whole god thing.
It seems, though, that I just can't catch a break with my elf romances. They messed up on Zevran in DA2 - I don't believe it was a flag bug but they just forgot he was meant to be devoted to the Warden. However, it totally ruined it for me that he was sleeping around with Isabella (and Hawke) when he was meant to be my Warden's LI. And since the Warden is off somewhere on their personal quest and Zevran is doing jobs for the Inquisition, it is clear they aren't together. Then Hawke reveals that she has sent Fenris away because she was afraid he would get killed defending her, when Varric has told me that it hasn't exactly stopped the death toll where he is concerned, so he's likely in just as much danger away - truth is having the LI around would have complicated the storyline so Hawke is alone no matter who they romanced. Still, on the face of it, another PC who is facing life alone. I was so hoping that this time around Solas would be for keeps but, no, the writers have other plans for him and so yet another PC has to continue alone without their beloved elf LI. You'd really think I'd have learnt my lesson by now.