It looks like he is stalking Bree, he has typical stalking motives. He wants her all to himself and he wants to control her. He's a nut!

But isn't there another motive?

Could be I'm missing something...

But isn't there another motive?
I agree...and I think it is likely revenge since she kicked him to the curb way back when and he is going to get revenge.

I can't remember now the details about her kicking him to the curb, but know he wasn't the one who wanted out of the relationship and out on his own after he became crippled.

Ok...here was what happened in season 6 when Orson and Bree broke up...

Orson, who had not known what Andrew did, (He ran over Carlos's Mom) calls out Bree on the hypocrisy of demanding he go to jail for his hit-and-run of Mike but hiding Andrew's crime. He is appalled at Bree for this and announces he's moving out.

Here is a link that might be useful: Bree

I think he wants to send Bree to sleep with the fish! He is definitely up to no good and I can not believe Bree is falling for his nice act after all they have been through.

I forget how he ended up in a wheel chair. Boy, Bree made a miraculous transformation from hooking in bars to domestic goddess again.

It is hard to remember what all has transpired over the years.

From the link below:
"During a neighborhood Christmas party, Karl tells Orson about having an affair with Bree and the two get into a fistfight inside a gingerbread house. Bree arrives to break it up and all three are inside when a crashing airplane smashes into the house."

See season 6.

Here is a link that might be useful: Wiki-Orson Hodge

Now I remember ..thanks..

You're welcome. Wiki seems to have the whole scoop on all the main members.