when you say fallen apart are there still fleshy bits left? if yes then repot these and keep fingers crossed. The gladioli are corms and I would expect them to be fine. The Dahlias may have rotted, all mine have over the winter as they got really cold and froze. So as long as they stayed frost free they should be ok.

Yes there are some fleshy bits left but they are soft like a rotten potatoe. I have planted them but dont hold much hope. They were kept in a cold place in the house so i dont think they were frozen. Thanks for the answer

Like Dahlias, the tuberous roots of Alstroemerias need to be connected to a part of the crown to grow, and you're right--softness is not a good sign. If they are still white or ivory-colored, though, there may still be hope.

What a shame you couldn't have potted them immediately and planted them into the soil when you got them.
The specialist grower that i buy mine from always state that they will be fine to leave out over winter as long as you mulch them to about 1-2" and they are - i leave mine in the ground, without a mulch and they're fine.

I would try planting yours out now and just see what happens - put them in a sunny area and keep them slightly damp, they should be sending up loads of new shoots now and if you've a very mild climate have about 2" growth.

Thanks all fingers crossed