Pulling Out of Depression

i am a 22 year old male

for a while now i believed that i wasnt depressed,

but my girlfriend is fed up with me and a previous job is not available anymore to me, because i would sleep in and not perform as expected,

i dont know where life is leading me and that upsets me greatly,
i know what my qualities are, but i would rather just waste it away,

i dont really indulge in any vices, such as alcohol or drugs,
i am not a gamer
for a time i delved into pornography as an escape, but it was short lived and i am definitely out of that stage
i just sleep, or chill somewhere,

people have described me as extremely emotional, and i could be really happy one moment and depressed the next,

it hurt my girlfriend very much, when we were dealing with an issue, and i sounded like i only cared about myself and in truth it was that way for some time,
she wants me to seek therapy, but i know what i need to do, i just lack the motivation to do it,

how can i show her and the people around me that i am changing and making myself better?

do i need therapy?

strangely, on the threat of breaking up, i didnt get more depressed, it actually made me commit more strongly to my responsabilities, but i dont know how long that will last, maybe that was just an initial rush, and i will just crash later

let me know what you think,