Mass-effect – I got an email from Ashley telling me to meet her at a Memorial but she is nowhere to be found

This video shows you where he is:

Note, Thane will not be there for your first hospital visit with Ash/Kaidan (when you go see them and Udina is there).

Thane video

Look at LessPop's answer for the word description.

The answer is yes, Spoiler:

but it will be after the assault on the Citadel by Cerberus.

Eventually, Ashley/Kaidan will be fully healed but will be recruited by Udina to be a bodyguard for the Councilors; Ashley/Kaidan is unaware that Udina and Cerberus are working together to lead the Councilors into a trap so Udina can take control of the Council. This puts Shepard and Ashley/Kaidan in conflict; Shepard must then convince Ashley/Kaidan into realizing the truth about what's going on and turning on Udina instead. If Shepard cannot persuade Ashley/Kaidan to back off, then Shepard can kill Ashley/Kaidan. If not, a squad member will shoot her/him.

If Ashley/Kaidan lives past this event, Shepard has the option of either recruiting her/him back onto the Normandy and into the squad, or of leaving her/him behind to assist with the War Effort.

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