When did Letty regain her memories?

Question

In Furious 7, towards the climax, Letty tells Dom she got her memories back. It raises some questions:

1. Was she telling the truth, or lying just to get through to Dom?
2. If she wasn't lying, were her memories real? (Because the wedding scene she remembers isn't familiar to the audience, I think.)
3. If she actually got her real memories back, why didn't she tell Dom earlier, when she did?

Answer 1

She actually remembers as she described.

1. Yes truth. She said

   I remember everything. It came to me like a flood.

   If you see the lift scene in the tower, when they were dressed formally and they said

   Dominic: To see you dress like this, reminds me f something

   Letty: of what?

   Dominic: Old times

   Then there was a flash where Letty remembered her past, specially their marriage day. We can see the same setup in both that memory flash and the shot in which we saw them getting married.

2. Yes it's real. Even a timeline is found of their marriage

   So where in that timeline did they get married? Based on some of those flashbacks—and the timing of it all—it would have to have been during Los Bandoleros. In other words, they got married between the first and fourth films.

   Long story short, they clearly tied the knot in the Dominican Republic before the fourth film, which means you should probably watch Los Bandoleros—if you haven’t already—to fully understand where all those flashbacks came from and what exactly it means for Letty to have her memory back.

3. Coz she didn't get the time to share with Dom. They were in a middle of a war. It's not something like saying 'Aw I got my memory back' It's emotional for Letty and a lot to digest after knowing that she's already married. It took some time to process it. That's why she didn't say to Dom earlier and was waiting for a private moment with Dom to discuss. But when she saw Dom dying she couldn't wait anymore.