Sleep problems

So my baby is 18 weeks old and is now totally dependent on me holding her to fall asleep. We established a great night time routine of bath at 6:30 and after I feed her while my husband reads her a story. I usually then rock her for 5-10 mins and put her in her crib and she’s out cold for a good 2-3 hours (about 7-9:30pm). When she wakes up around 9 to eat again, that’s when we move her into the bassinet in our room. I’ll feed her again and then put her in the bassinet. 75% of the time she wakes up with in 15 minutes. I usually let her wriggle around and fuss a little (she never get into a full blown cry) until I have to pick her up. The second I pick her up she’s fast asleep. Literally in a matter of seconds the pacifier is out of her mouth and she’s dead to the world. ill leave her there for a few more minutes and put her back in the bassinet and the cycle starts again. Last night it scared me though because I woke up with her still asleep on my chest 4 hours later. I didn’t remember falling asleep. She was fine thank god but I don’t want that happening again. I’m thinking she’s gotten dependent on me holding her for the past few nights. She naps on me too. But with other family members, she has no issue going down with out being held. Idk what to do! Any one have any ideas on how to break the dependence/help her sleep. The pediatrician wants us to wait until she’s double her birth weight before we start sleep training. So she still needs to gain about 2lbs.