Bodhicitta is not the opposite of egotism. You don't throw yourself on the floor and invite everyone to walk on you, nor do you throw yourself off a bridge. All of that suggests there is a self you're supposedly sacrificing. The examples you give of someone giving all their money away and becoming destitute, or as I often struggle with, consistently letting myself be used by others for apparently selfish means, that shows the lack of wisdom in the "selfless" approach as well.
The problem is when you keep "self" in the picture, you just transfer the problems. There has to be wisdom in the intention or else suffering follows in the wake even of apparently selfless action. It may perpetuate the suffering of others by letting them get what they think they want. That suffering is caused by ego-clinging, just as if you had done the opposite and been greedy or spiteful.
I think you're perhaps a bit too fixated on results and ends instead of working on the mind behind everything. I would suggest just continuing practice and not worrying so much about vague ideals, like TMingyur said. You'll find that small opportunities to practice generosity will arise of themselves, and you'll start to do them as naturally as you would saying hello. That's karma at work
Of course, it could be argued that one of the goals of practice is to adopt the view that you as an individual does not matter as much as other people.
This isn't the goal of practice in this area. The problem is our dualistic worldview, us/them. No matter which we place in superiority to the other, them over us and call it "selfless," or us over them and call it "protection," the basic view is flawed. That view is "self".
One of the things Buddhism addresses in depth is these notions of self and other people. We attach simple labels/ideas to things then try to impute them as part of reality. No, they are descriptors that are very vague, even "self". The fact that the result of practice may appear to be selfless acts and putting others over oneself says more about our unenlightened viewpoint interpreting enlightened action into what we can understand.
Ultimately, you can begin to let go of clinging to yourself, your ideas of how things should be, how others should act, and even how you should act. It's not yourself that is the problem, but the view. You don't just throw everything out and become some soiled rag Buddha that others use as they see fit. It's more about getting in touch with the rich spontaneity of the moment. Out of that comes a natural generosity and light-heartedness akin to setting down a heavy burden. That burden is the self.
You often hear people who act heroically say, "It seemed like the natural thing to do," "I didn't think about it," "Anyone would've done the same thing," etc. Under duress, their egos didn't seem so important as the realness of the moment right in their faces, so they acted within that framework. Surprise surprise, selfless acts bubbled forth.
In imitating or aspiring to behavior (such as following the Precepts), we can get a taste of the state of being that drives them. It's not at all about striving and struggling to be Buddhas. We already are Buddhas. The trick is getting in touch with the naturalness we already have. Then generous action is the cart that follows the horse
Basically, practice practice practice!
Save yourself, then you can save others.
Please take the above post with a grain of salt.