They say that insanity is doing the same things over and over and expecting different results.
So if what you're doing doesn't work, try a different approach.
OPTION: Try writing the verse first. If you write using a guitar, switch to a different instrument. Even the smallest change from the way you normally do things can result in totally different results.
OPTION: Force yourself to write a verse or three. I think the biggest fear to writing verses to what we perceive to be a really good chorus is that the verses won't live up to the standards we have ascribed to that chorus. Very likely, this is nowhere close to being accurate. If you're at the point as a songwriter where you can't get verses written to a chorus, you still have a long way to go. How long, is totally up to you. So start forcing a few verses even if you don't think they work well..... do SOMETHING to get some forward momentum going. This notion that you have to be "in the mood" to write is utter nonsense spouted by folks who probably don't write often and use that as their excuse for not writing more. Once you start to write, even if it's a forced writing session, very often, you will get into the mood as you start to be creative. The more you do it, the easier it becomes. Once you break through that barrier, you may find that verses are just as easy to write as choruses.
OPTION: Find a cowriter who can help finish the songs. Look through the folks you have available here in the Cakewalk forums. Quite a few are songwriters. Listen to the music on their music pages and find someone who writes in the genre that you do. PM them to see if they're interested. Don't ask a writer who writes rock and hip hop to help you write a country song and vice/versa. Some of my best writing has been done in the various collabs I have been involved with through the years.
OPTION: Join a group like The Nashville Songwriters Association International. As a member of this songwriting group, you have access to their extensive video library. You can view video seminars put on and hosted by some of the world's best songwriters as they talk on everything from song structure, to lyric writing, working with collaborators, melody, to the business end of this musical thing we all do. While the name would indicate they are country, and they are, they also have staff who are experienced in rock and many other genre's of music. In addition to the online video library, you have credits to submit 12 songs to their staff for a professional, detailed, honest, evaluation. It was by using this service and submitting several of my songs to them multiple times, after making corrections they had suggested, that I managed to get those songs into top shape and the songs were ultimately signed by publishers.
There you go...... only you can decide you want to move forward and get better as a writer.... it takes just doing one or more of the things above. As a writer, you never stand still.... you're either moving ahead, or you're moving slowly backwards. One more thing..... unless you write, write, write, and don't worry about how the songs sound..... just write, you will have a hard time progressing to the next higher levels. Jeff Steel, hit country writer with over 24 number one hits to his credit, writes one song a day, every day. Most are throw away songs..... but those gems in the bunch..... those are the ones that make it all worth it.
Now, go and force one of those songs and see what happens.
EDIT: One more thing..... do NOT worry about the arrangement or the solo's until AFTER you have successfully written the song. It's way too easy for folks like us, who enjoy the recording process as we do, to become distracted with "building the song" before we actually have a finished song to build. Write it first, then tinker with the arrangement to your heart's desire.
Some advice I got from the NSAI folks on my tunes that they gave advice on.....
Keep intro's as short as possible... get into the song quickly
No one wants to hear fancy guitar solos.... if you must play one, use a short turn around
The Chorus needs a monster hook.
Get to the chorus before the clock on the song hits 60 seconds.
Be done before the clock on the song hits 3:30... or there about.
Of course, this doesn't apply to every song.... but that is the commercial country basic formula currently being used as writing guidelines.