I'm sorry to hear that you have had some tough times getting through school. Have you identified where/what area(s)you are struggling with? I hope your schools have helped you in this matter and discussed with you what you need to do or change, if not, I would get with them to find out.
I am very sad to hear that your husband is not being more supportive. My husband is even appalled at his remarks to you. Regardless of how much you are struggling with this, your family shouldn't kick you while your down.
If you got to your last semester in an ADN program, wouldn't that mean you've already completed the LPN portion? I'm in an ADN program now and after the 1st year (we go by quarters), we can challenge the LPN boards. Have faith in yourself. When I decided to try for a RN career, I kept being told I'd make a great PA or Nurse Prac. I know myself too well and do better with "baby steps". Granted they do differ, but there are many nurses that go on to be PA's. I feel better when I really "know" the first level. I feel more confident moving up onto the next level. There is no such thing as "just an...LPN" or RN, etc. Every level and job is just as important as the other. Set out to be the best damn LPN!
Show everyone that taking a couple steps back does not mean you are there forever (or that you are "too stupid"). Remember, it doesn't stop with school. There are some that can pass school with flying colors but struggle to pass the NCLEX. I know I didn't specifically answer your questions, but I hope that I can pass on a little bit of encouragement to keep you on track. Since I don't know exactly why you are struggling to get through school, it's hard to say whether nursing is the right path for you. But you know yourself better than anyone; so if it's what you want, get on that phone and find out what you need to do to get there. Think about standing on that podium saying "when everyone said I couldn't do it, I did"