to Native speakers:
What's the difference in meaning between sentence 1 and 2?
1. I thought you loved me.
2. I used to think you loved me.
1. I loved you.
2. I used to love you.
hmm i don't think there is much of a difference, except "used to" is sometimes used just to emphasize the fact that the action does NOT happen anymore. this is how it seems to me. using "used to" is just a stronger way of indicating that that action has ended. anyone else have something to add? because i don't know if that's a very educated explanation.
Suppose you've just found out that your boyfriend/girlfriend did you wrong, you might say "I thought you loved me."
Suppose you've been going out with someone for a while and for the first time they say "I love you.", you might reply, with a smile, "I thought so."
If you say "I thought you loved me.", you could well still think so or at least it wasn't so long ago that you did (unless otherwise specified).
However, "I used to think you loved me." implies that it's been a while since you changed your mind.
Similarly "I loved you." refers to a past situation but "I used to love you." emphasises the implication that it is no longer the case.
There is no difference between the two sentences. They are both present tense.
Sorry. They are both PAST tense.