Let us roll all our strength and all Our sweetness up into one ball, (lines 41-42)
This is probably the one image of sex in the poem that isn’t loaded with irony and sarcasm, cruelty, or violence. It is genuinely playful, direct, and clear, with less room for ambiguity.
And tear our pleasures with rough strife Thorough the iron gates of life (lines 42-43)
The speaker suggests that they can use the difficulty and frustration of life (that is, "strife") to enhance the sexual experience. This line would be easier if it said "and tear our rough strife with our pleasure." Then, we could say that he wants to use sex to help him cope with the pain and frustration of life. But, that would be too simple for our complicated speaker.