I wish I could memorize the Thai alphabet. I can read quite a bit now, but learning that alphabet has proved to be an impossible quest. Old dog, new tricks.
Don't really need to.
Start with 10 or so consonants and a couple of vowels and you are on your way. add to it gradually.
Just look at signs and stuff and you'll soon see a pattern emerge.
Took me about 3 months (an hour or more every day) to read fairly proficiently, though I haven't a clue what a lot of it means.
It's really not rocket science and it's also a little bit daft to be illiterate in a country that you live in.
Perservere with it and you'll start reading signs when you are stopped at the traffic lights and stuff.