Drop Down List With Blank Cells Throughout Range.

I've used this site for help many times, but this was the first time I couldn't find the answer to my question through searching. I've looked all over this site & elsewhere, tried 2 dozen different solutions, and nothing seems to work.

I've used a budgeting spreadsheet for years, which lets me plan bills weekly according to paychecks. For each month, going down the "Expenses" column, there lists are seperated by when they'll occur. So there may be three blank cells, then electric bill, mortgage, blank, blank, cable bill, blank, cell phone, blank, gasoline.

On the checkbook worksheet, I want to enter a drop down box for the Expenses. The problem is, every solution I've found for doing this is aimed at eliminating blank spaces at the end of the list. This by necessity has to have blank spaces throughout the list, but I would like them to disappear in the drop down menu.