"Teen Mom" star Rachel Beaver is speaking out about her alleged texts with Lil Wayne ... saying she's just a single mom trying to cash in on some free trips.

Rachel tells us she had to do a double-take when she saw rapper Lil Wayne had responded to her drunken outreach ... adding she'd like to debunk any claims that she's a gold digger or "begging for a flight."

She says Wayne's millionaire status made taking him up on a free flight to come see him a no-brainer ... "I don't care if you're Lil Wayne or Joe on the corner ... you're paying for my flight ... that's how I roll, and that's just how it works."

Rachel addresses backlash on why she decided to release the texts, telling us her hometown friends are big fans, and she wanted to flaunt the exchange.

Since the texts leaked, Rachel says several other men have offered her free trips -- so she's doing just fine without Wayne.

As we previously reported ... in alleged texts obtained by TMZ, it appears things started with Rachel -- who is currently 23 -- sliding into Wayne's DMs on November 13 ... writing, "Fly me out I won't say anything like the last one."

It looks like Wayne then asked for her phone number before the conversation moved to texts, which allegedly show Rachel suggesting they wait to meet up until after Christmas because she'd need time to line up a babysitter for her children. Then, on January 3 around 5 AM, it appears Wayne reignited the conversation with a simple message -- "want u."

From there, it looks like the texts continued on and off for weeks ... with discussions of travel plans, before things eventually died down ... or she got blocked ... and Rachel got a new phone.

Rachel tells us she'd still be open if Wayne wants to fly her out ... your move, Weezy.