at level 25 there isn't any real easy way to manage your force.
However : move back the 3 points from eletric induction and the 1 point in blood of sith back to the heal tree.
Go get ressurgence, and especially force bending. Then get the lower cost/lower cd bubble. This imo will help a lot more than a passive 9% force reduction, as you'll be casting DI with a 30% one nearly all the time.
Your "bread and butter" heal only comes at level 30, and with it is linked the main force management.
At 25, you need to watch for :
-be careful not overheal. That means using a heal for a too small amount of health that is actually going to be gained back. Ex. throwing a 3k heal on someone that needs a 1,5k one.
-However : stay off Dark Heal. Unless your target will die by the time you cast DI, don't touch the thing, its horribly costly per health points given back.
-Use your bubble smartly. It can be your best heal, or your worse overheal, depending on how you use it. On DPS, never unless you need it to load a DI because they pulled something they shouldn't, or that they are going to be taking a short burst of damage that is predicatable. Ex : the mining droid on hammer station.
-Keep resurgence on the tank, as well as you, so that will take care of :
-1 use of consumption, never more than 1 stack and you have your "best" force regen. Consumption is always "force positive" but after 2 stack, you enter a spiral that makes it your only way to keep force up, which you pointed out is horribly expensive. With it and your quick-self heal, Unnatural preservation, that should take care of whatever health you put in it. Also, try to use the most of UP as you can, maybe even waiting for 2 consumption usage before popping it.
Doing that, you are doing as much as possible to last. Now, keep in mind you are not alone in the party, and there IS a certain limit to how long you can burst heal or keep a certain constant HPS. Of course, your gear should be adequate for your level.
Sorc in particular at your level do not deal well with burst, and their ressource will go down the drain very fast, and issue is, each burst, especially at your level, will lower your ressource, where as other heal class just suffer from a quick "low regen" they have ways to overcome.
So if you are still unable to keep people up, do check the following:
1st -is the tank really a tank, or a dps that queued as tank? Even worse, some don't even bother respeccing or at the very least using the "tank stance". If the answer is no, its easy to guess he may be taking way too much damage, which in turn pressures you. That alone may not be a team-killer, but if you combine it with :
2nd- Are the dps quickly killing the trash to reduce the ammount of incoming damage/are availaible CC used smartly and remain unbroken to help you through?
3rd - are the dps pulling some stuff from the tank, either due to a tanking issue or to a dps having a bad target priority list, that cause them to take uneccessary damage?
4th - Are everyone avoiding damage that CAN be avoided, such as powerful ground targeted AoEs?
If you end up in a good group, with a good tank, you'll be bored out of your mind and end up helping with dps, altough again with sorc ressource mechanic it IS trickier than with say an operative, since giving 1 force in attack can quickly mean 1 force you ain't putting in healing.
Eventually, you can decide it is a personnal failure if someone die in your party. I was like that at start.
Then I realized I have no heals or cleanse for stupidity. And suddenly, unless its the tank, leaving the idiotic dps who just keep making your job harder die can quickly teach them to behave.
If its the tank who is not very good, well jus be ready for a bumpy ride. But so long as you keep your rotation smart and follow the first pointer, you can rest easy knowing you are NOT the one with issues.