What you believe about your spouse and thetrut about your spouse are not the same. Always. The best you can do is gain a closer approximation of who you are married to.
Let's assume I'm right in saying above. If I am right, then some people would be very discouraged by the fact that they can't know your spouse fully. It would feel risky. It might feel unstable or insecure. There might be the fear that not knowing is bad and therefore there can be no trust.
On the other hand, some people would be energized by the fact that they can always, even into old age, learn more about their spouse. There is no cause for boredum in marriage when there is no limit to what you can continually learn about your spouse. These marriages do not get stale or stuck. There is the constant sense of hope, of wonder, of intrigue in the marriage hat can never be fully known.
Going a little further, not only can you not gain a complete knowledge of your spouse, your spouse does not remain the same. So, even if you were to come to complete knowledge of your spouse today, she or he might not (will not) be the same perosn tomorrow.
So, in order to know your spouse as close to the real spouse you are marriage to, you must be willing to challenge your own "knowledge" about him or her. You must deconstruct your beliefs and reconstruct you understsand according to what is happening in real time.
What about the past? Yes, it matters, but we cannot remain there. The past is part of the accumulated present and anticipated future.
You may not be loving your spouse until you deconstruct her or him.