According to the property manager I would have to get my security deposit (I contributed 100%) from him if I move and he stays in the apt. Is that legal what they are saying or are they just being lazy and don't want to ask mu roommate for it?

Yes, it's legal. When the landlord receives a security deposit it is considered as coming from everyone who is listed on the lease. They do not have an obligation to return a portion of it if one of the people on the lease moves out. The person moving out has to get their share of it from the person who is staying.

Then why did they require my roommate to write s note stating that he didn't contribute any money for the deposit Lisa?

I've never heard of a landlord or management company doing that. Is your property manager new at their job? The landlord isn't required to return any of the security deposit as long as there is still at least one person living in the apartment who is listed on the lease.

Lisa, the woman who told me that my roommate had to write s note stating that he didn't contribute any money to the security deposit has been the on landlord for 30 years.

A guess is that this woman was trying to help you out, asked the roommate for the note, and then was over-ruled by her boss (the landlord) who, perhaps on the advice of counsel such as Lisa, decided that paying the deposit to OP would be dicey even with the note.

I have to agree. She probably thought it was the right thing to do and then discovered otherwise.