What are some things you've been lied to about in a relationship?

Or! Bonus question, lies you've told in a relationship?

Unfortunately, I think my partner *might* have lied to me again. In the past it was a white lie and they made up for it by rebuilding trust and they have been honest & transparent.

The long story part if interested:

Something just feels and seems "off", my partner is NOT a planner, yet apparently planned something. I plan everything we do. And, it's not something that seems like they'd look into themselves, but I am all for expanding your horizons.

I know they hung out with and kind of like another person, a woman. We discussed being polyam just last week because of it. And my partner was very honest, about having hung out with this person, wanting to pick me, but having a hard time not being taken by this person because they are new.

The only thing I mind is how this effects my relationship. I don't like the idea of denying my partner connection with others. I'm not going to say who they can hang out with. But I also know from experience that hanging out with people you like when in a relationship can be like playing with fire.

My partner agreed to be polyam after some deliberation. Then, the next day, I asked, they said no, they do not want to and didn't see a reason to do so. They don't seem to want the complication, and I get that.

I do trust my partner for the most part, I have a lot of faith in them, and I have plenty of self esteem these days. I don't want to lose them, but I will not be lied to. I don't need my partner in order to be happy in my life. I'm glad we shared what we did and I'm happy I moved closer to them, but not too close- because my area is cooler!

Anyway, they told me the class they are taking is one on one, but online it says group. I am going to call them to ask about the classes, I guess... something feels fishy.

Like I'll be proud if it turns out they actually did plan this by themselves lol, they have a seriously hard time with that, and ask me about some pretty basic things, due to their mental disorder. But they have also done a lot of growing lately as a person.

And I think if I ask they'll tell me the truth, I just, don't know why they wouldn't when we discussed everything last week, and they brought up considering taking this class, I said we could do it together & they said no, it's a one on one class, then the website says something different, they said thet weren't going to talk to the other person- completely their own decision, and I didn't plan to be upset whether they talked or not.

But if this class was with the other person... I don't know why they wouldn't just show me the respect and tell me. At any point.