The first thing that we assume is that the GTVA runs under a Capitalist society, which we don't know for sure is still in effect. Assuming it is, i would estimate that building a destroyer would be roughly equivalent to the amount it costs to build a Ship today. We could probably estimate all the processes of building a spaceship to that of a naval ship nowadays. This number would probably be highly inaccurate, but its the best that we can do. Also, we don't know what the economic state of the GTVA is, whether or not they would be able to even fund a massive rebuilding of its space fleets. The relocating of capella refugees would cost massive funds as it is without outside sources. Then after finding somewhere to relocate, they would have to fund the colony and help it set up. This is not a quick process and would probably take quite a long time, taking up even more funds. Money doesn't grow on trees, it has to come from somewhere. If the GTVA is NOT capitalist, and can just use whatever resources it wants, then we have to wonder whether or not it HAS the resources to build all this.
As for terrans feeling "safe" and "terrified", i don't see how safe they could feel at this point. They have been shown that the shivans can pretty much come in at any time and blow the crap out of anything the GTVA throws at them. Not to mention the 20+ Sathanas still out there. If anything, they would feel less safe than they did after the first great war. At this point, one would hope that propoganda could swing this in a positive light, but there really isn't much they could do. Capella was completely wasted, and the only way for them to stop the Shivan advance was to blow up one of the Knossos nodes. As for being terrified, they're just as likely to feel that the GTVA is unable to protect them, and join pirates as they are to hide in their homes and hope for the best. Especially when word comes to them that outer systems are being controlled by pirates and the like.
As for reopening the sol node, do we know what level of technology the GTVA is able to achieve? Can they replicate the technology to re-enter sol? If they can, why haven't they started mass producing nodes to better allow economic trade lines? If they could do it, it would also require resources that may or may not be available to them. If they can't, then they would probably need to spend several years researching and developing this technology to something safe and usable, which would also require more resources.
morale is good and all, but it doesn't put food on the table.
The bottom line is that the next few years for the GTVA are looking grim. They're going to be going through tough times most likely worse than our current predicament. Imagine our situation, except the state of California just got destroyed and rendered uninhabitable and all the survivors are in the surrounding states in need of proper housing, work, food, etc. i don't think this will be solved within a few years, ten years would be a more realistic estimate, and my pessimistic side is telling me it may even take longer than that.