"I miss being with you." might be a start. Instead of asking directly, you are simply stating a feeling that she does not have to act on or reject.

Then build up gradually. "I miss touching you." "I miss you touching me." Again, not direct demands, just simply stating a feeling.

As you grow more confident, try personalizing it to your own lovemaking. "Remember that time when... Do you think we could do that again sometime?"

And I must be missing something here, but how is expressing a need to your partner offensive?