Mom issues

So I only see my mom on Tuesdays. I didn't really care back then but now I do. She thinks that taking me to myrtle beach or giving me a dollar or two will make up for it. I don't think she cares about me at all.....We barely hang out and she is always locked up in her room. She is always drinking. I feel like a mistake. but I believe she favors my 18! year old sister. Since she lost her dad almost 6 years ago. I feel like an unwanted child. My dad is always paying to get my hair done, pays for my shoes, clothes...even takes me to Forever 21. I love my dad but my mom blames everything on work....I got work this, I got work that. Like ik that I should be greatful, but my it feels like I mean nothing to her. She has a COSMETOLOGY LICENSE! She worked at a hair salon. But can never do my hair. She has a high paying job...I love my mom but I don't know if she loves me.