This question is perplexing! Unless you consider the entire poem to be an expression of verbal irony (hardly Bradstreet's style), its content and employment of various poetic elements create a strong and unified expression of Bradstreet's deep and lasting love for her husband. The first couplet establishes the tone and theme of the poem:
If ever two were one, then surely we.
If ever man were loved by wife, then thee.
In the context of Bradstreet's strong Christian faith, her allusion to two people being one reflects her belief in marriage being a spiritual union. Thus she presents herself as a woman who loves her husband and is joined with him in the most profound way. Throughout the remainder of the poem, she expresses the depth and passion of her love, celebrates it, and prays that her husband will be rewarded by heaven for his devotion to her, since there is no way she can repay him.
The only word in the poem that invites any conflict in interpretation is found in the final couplet:
Then while we live, in love let's so persevere
That when we live no more, we may live ever.
If the word "persevere" is interpreted in terms of enduring to complete a difficult task or journey, then it might be argued that she sees their "love" as only a matter of Christian obligation to be honored so that they have eternal life after death. Nothing in the poem, however, supports such an interpretation. It is more consistent within the context of the poem that "persevere" is chosen simply to mean "to continue strongly." Her hope, in these final lines, seems to be that she and her husband will love each other so deeply that they will not be parted, even after death.