The fundamental halacha is that it is permissible to have relations the night prior to an onat veset. There are fairly widespread customs to observe a full twenty-four hours for the onah beinonit or to observe the onah before any veset (Or Zarua).
Even if you follow those customs in general, you may have relations in this case, when it is so important to you as a couple.

We hope that this helps. We are concerned by your statement that your husband doesn’t have time for you during the week. Even if he is objectively very busy, it speaks to a disconnect between your needs and his response to them that you might want to speak about with him, or with a counseling professional. Please let us know if we can be of further assistance.