Your dreams, in the aspirational sense, are your hopes about the future. They guide your present actions towards a larger goal. Your memories are your links to the past and inform your decisions. Both elements contribute to who you are as a person.
In youth we have more dreams than memories. Then the memories accumulate with age. At some point, you may have more memories than dreams. Then you might be living in the past more than you are hopeful about the future.
It may be that having more dreams than memories is essential to maintaining a young spirit. Still, remember: past and present are in the mind only. You are now.