I'm no expert but you could try training her (without you in the saddle) to always back up after she stands next to it. This could stifle her urge to walk forward.

I was having a similar problem with my horse but with her stepping away from me once I got on the mounting block. I started teaching her to stand still no matter what, she cannot mover her feet until asked to. Technique can be found in 'Dually Halter - standing still' video lesson. I do not have a dually but a standard rope halter will work similarly. I then had a friend help do the schooling of her to stand still when I was pretending to mount eg, gathering up the reins, stepping on the mounting block etc, schooling her on the halter when she tried to take a step away. She now stands well when I mount and will not walk off until I ask her! and be careful not to bang on her sides when trying to get feet in stirrups, this will give mixed signals. Hope this helps!

Wabbit--

It wasn't clear from your post if you warm your horse up before you go to mount. If Molly has any pent up energy, that could cause her to go walking off without waiting for you to be settled. I have created the mounting block as a "sweet spot" (a spot the horse likes to be). Here's how: I warm my horse up and then use the mounting block as the place she gets to rest for a few minutes BEFORE I go to mount. Don't shorten the time on letting her stand there, and do rub on her and let her know that this is a good place to be still. Remember that horses consider rest a reward.

She also went thru a phase where she tried to walk off on me and the recommended method in Monty's video handled that. The other suggestions posted also seem quite practical.

I know it may be tough, but if you are not spry due to your injuries and cannot train Molly on your own, you do need to find someone to help you with this issue, even if it means paying someone for a short period of time. It wouldn't have to be a pro (although that would be best). Someone willing to prepare to mount as you are on the lead schooling Molly would do the trick--perhaps there's someone at the barn who would take $10 for a half hour's work, a few times a week? Molly walking off before you are settled in the saddle is dangerous for both of you and this issue should be handled to your satisfaction before you continue riding.

Thanks all for the comments, I have been offline for awhile and am back finally. My good laptop has to get a new motherboard, thank goodness for 3 yr warranties! I have an older one I am using for now. I have been working with Molly on standing and being able to lengthen the distance including mounting the stairs while holding the line. I can stomp etc and she does not move, I had someone hold her while I got on and did not get my feet in the stirrups before she tried to walk off. If I can get the lady at the barn to help me I will. Molly is a strong willed girl, and I do walk her alot in stages. I did just get here a bitless bridle and boy what a difference in attitude! She walks with me before tacking up and then once saddle is on, then again once bridle is on. I will try the rest at the mounting steps sounds good. She trys now to take me there after a bit of riding as if to say is it time for you to get off now? LOL! Anne

BTW, Julie how do you warm your horses up? Everyone at the barn lunges and I agree with Monty on the damage you can get lunging. Once it is warm and I can use the round-pen again I want to try driving like Monty's lesson shows. That would be a good way to warm her up. She will circle the roundpen when asked as she was trained previously to view it as a work place. They had one up inside the barn for winter but others riding thought it was in the way and I was not able to make it out much over holidays so they dismantled it. Anne

Wabbit-

I vary my routine when warming my girl up. We are all indoors during the winter, as winters in OR are wet and long, and usually somewhat snowy. Using the round pen is fine to free lunge, as long as you don't wear that out. My mare seems to get bored with that quickly. I also have the luxury most of the time of turning her loose in the arena and letting her run and buck if she wants to on her own, with some encouragement from me. We are well joined up, so having her come to me when she's calmer isn't an issue. If others are also using the arena, I will get her on a lead line and have her walk with me, practicing her side passes and basic manners along the sides of the arena and the round pen in either direction. Sometimes I'll lay a barrel down and ask her to jump over it, after jumping over some smaller, homemade jumps (pvc pipes with red tape for visibility, set up on plastic buckets filled with sand, with notches in the top to cup the pipe- only about 12-18 inches high); sometimes we will trot in hand and do backups thru L's. The point of warm up is mostly to make sure your horse is with you. If you feel Molly needs more physical warm up, you can always walk her while riding, doing a review of her steering and stopping skills until you feel she is moving easily. Oh, FYI: my mare also tries the stop by the mounting block :) Just ask her to move off and have her work for a few more minutes so she doesn't make a habit of it. She's just trying to control your feet instead of you controlling hers. Have fun, and keep working until you get her to stand like a lady when mounting. It can be done :)