Answer:
1- it will have the ending -se.
In the infinitive form: dormirse, bañarse, peinarse, vestirse.
Once you conjugate a reflexive you must add the appropriate ending:
Yo- me
Tu- te
El/ella/ usted-se
Nosotros- nos
Vosotros- os
Ellos/ ellas/ ustedes- se
Yo me baño
Tu te peinas
Nosotros nos dormimos a las 10 de la noche.
If you conjugate with gerundio ((-ING endings). You must combine with the verb Estar just as you do in English :
Yo estoy bañANDOME., or Yo ME ESTOY bañANDO I am bathing myself.... or I am showering.
-Ando is the ending for verbs ending on -at and -iendo is the ending for verbs ending on ER or IR the equivalent of verbs ending on ING in English
2. Estoy enamorándome means I am falling in love
Or you can also say: ME estoy enamorando.
3. You are right, la leche se está acabando or la leche está acabándose
4 As previous examples you can put the reflexive pronoun before or after the verb
