Bend or Portland?

My husband and I will be traveling to Oregon at the end of Oct (thurs-Monday). We will be heading directly to Bend when we get there and we are planning to head back to Portland Saturday morning to spend a couple nights there. Is two nights each enough? Should we stay the entire weekend in Bend, is there enough to do? It will be Halloween weekend and we are visiting friends so don’t know how lively the town is.