I have a lack of trust

See a therapist. I don’t mean this in a rude way, insecurities live in everyone. 2 ways to deal with it: sort it out, or suck it up and never say anything about it.

Is there really any reason for you to be insecure? Maybe ask her about the friends so that you at least understand what is going on

Currently my SO has lied to me countless times in the past she's doing really well in not lying but I can't seem to trust her after how she's hurt me. I don't want to break it off with her cause I do love her and want to make it work, I suffer from panic disorder, anxiety and severe paranoia and repetitive thinking which is hard to cope with, I'm fine with her making conversations with guys as long as it isn't sexual in any way, but when it comes to friendships and meeting up my anxiety kicks in and I start panicking I don't want to be restrictive so I just say it's ok when it's really not I can't deal with this and it's getting to me anytime I say something like I don't want her to meet a friend of the opposite sex I feel horrible so I just don't say it . Any advice?

just chill out bro

Not that I want to make you feel even more insecure, but how do you know she's 'doing really well in not lying' to you? Doenos she have a tell that you missed previously but are now aware of?

Anytime I had asked she dismissed it and acted as if I never asked she A) Tells me a day before she meets them or B) Doesn't tell me at all. I am seeing a counselor and a therapist I have severely bad mental health. She never tells me what they are doing when they meet up she never keeps me updated on what they are doing.

She is under no obligation to keep you updated on what she is doing with her friends.

Your best option here is to break-up with her. Once someone breaks your trust that's essentially the end point. Relationships don't work without trust, and once it's gone it generally doesn't come back.

Sounds to me like being single is the best thing you could do for your mental health right now. Relationships make conquering mental health issues so much more complex. You should take some time to work on improving yourself and then when you feel more ready find someone new to date.