This can be uncomfortable to talk about, especially if you have struggled with mental issues, but this is something that will have a huge effect on your marriage so it is really important you are honest now.
So talk about your current and past mental health issues.
It is likely that if one of you suffers any mental health issues you will need the support of your spouse. So if you suffer and haven’t made them aware then you can’t blame them if down the road you find they are unable or unwilling to support you.
Yes, I know this is a sensitive issue. But it needs to be talked about now.