Me:20m her:18f what do I do about this bad anxiety

I’ve been in a relationship for about 2 months and I’ve known this girl for around 3 months, the first month before we were offical everything was great and nothing was wrong, two days after we went offical I’ve had this crushing anxiety and overthinking, for the last two months I’ve been trying to figure out reasons and I’ve blamed so many things over the overthinking aspect, “am I loosing feelings? Is she going to leave me? Is this anxiety going to ruin us?”. Some weeks have been better than others and I’m in therapy for GAD (general anxiety disorder) and it’s been alright and I’m started meditation this week which should help a lot, my anxiety has shifted towards her being very hopeless and upset, she’s been so supportive and I haven’t listened enough because last night I cried to her again because of my overthinking and she asked me if I was happy in life and I said no, she went really upset questioning everything like if this anxiety will go away and will we get better and she genuinely just feels bad for me, she said will not leave and I’m saying the same things currently because every relationship has bumps, I just am in a state of a lot of anxiety, but luckily today I’ve been better and dealing with more “self reassurance” other than leaning on her, I understand completely why she’s upset it’s just hard for us both