I don't think you'll be walking out of the dentists office tormorrow without your teeth. If the bonding doesn't work the only thing you're likely to go home with is more decisions to make about what to do about your remaining teeth. I hope the bonding works. I think your decision to save as many teeth as possible is a good one.
With only 7 lower teeth remaining I'm surprised you don't already have a lower partial denture. I think you need to face the fact that you'll need a lower denture sooner or later whether or not you can save your last remaining teeth. Where your appearance is concerned, a lower denture can only improve it and you, your children will have nothing to feel embarassed about. I hope that your husband is being supportive through your dental problems.
If you've only had the upper denture since June of 2003 it's not surprising it's causing you so much grief. It takes time and patience to adjust to dentures. Three months is barely enough time for your gums to heal never mind learn how to eat with a denture. Have you had any soft relines done? Have you had any adjustments?
Having to get dentures in your 40's or 50's is traumatic enough both physically and emotionally. At 29 I can't even imagine what you must be feeling. Talk to your doctor if your physical or mental state worsens.
By the way, I'm 49 and have had dentures (full upper and partial lower) for just over 9 months.