I was told my marriage isn't legal and now I want to have the married title removed without divorcing...

if this marriage was truly invalid, you may be able to have it annulled. I know they are not inexpensive however. There would have to be a trial in addition to every other single piece of paper that you have to file for divorce. Or almost. Bottom line, an uncontested divorce would likely cost less.

It's a lot cleaner and more legally binding, if you obtain a judgment of nullity. You can do an uncontested nullity, or even obtain nullity by default. The "trial" is a 5 minute "prove up" hearing. UNLESS, the matter is contested - which it sounds like it won't be. I've done a couple of these recently. You are not alone and your situation is not unusual. It happens more often than you'd think. Real easy to "fix", but you do in fact have to go through a legal process to have the marriage nullified.

If not done right, it could be costly. I would go back to the lawyer who married you and see if they will handle the annulment at no charge go you. Otherwise, you will need to hire a lawyer.