Summary: When I'm single I revert to the alpha that leads me to sleeping with/dating interesting/hot girls, but once I find a girl to LTR with I slowly convert to beta and it fizzles out and dies... How do I stop this!?

In recovery beta here with a simple question and then a longer backstory.

Does anyone else seem to phase into red-pill alpha when single, seeing multiple girls, supreme confidence, and then when finally finds a girl "worth" a LTR slowly regressed into Beta? I've lost 3 relationships now with this pattern (with different lengths), but after this last one I decided to dive into TRP and read the entire sidebar and top all time posts and felt like I was reading a fucking diary. Scared the shit out of me. The girls I pulled for LTR were all awesome women (smart, sexy, totally into me and fun) but eventually it fell apart when I got too passive, beta, and it disgusts me because somehow I have been losing my alpha as a relationship progresses.

This was always explained (during the breakup) as us getting 'too comfortable' or 'relaxed'. I love to cook and loved to 'take care' of these girlfriends and in the end eventually felt taken advantage of and the sex dried up and yada yada yada WTF.

When I met my 4 year LTR at the end of college I had just finished reading The Game by Strauss and had participated in forums and PUA stuff for a year that I was single, and it was single-handedly the only reason I pulled this girl. LTR lasted four years but by the end I was your stereotypical BB and I'm worried it's going to happen again.

What do you do to avoid this pitfall, has anyone else slipped into this pattern? I know lots of users here affirm that they're 100% AF but surely there are others like me?

Some background on myself (And the reason thankfully I'm able to even step back and consider this unlike my still plugged-in friends): I'm a successful business-owner doctor, 29 years old, decent looking, funny, motivated guy who likes to travel and experience new shit. I'm typically the life of the party and the one my girl 'friends' say can't believe that I'm single (or not married, etc etc). But I loved to pamper my GFs, I love to cook, I love to go out of my way to show how much I loved them, etc, etc... all for what? Watching my guy friends who are seemingly total dicks to their LT GFs get more action and more out of their relationship than me? Than me, the guy who was 'such a great guy, perfect to me and so kind, so much better than my previous relationships' <-- actual quote from last 4 months relationship that ended (head spinner until I unplugged again)

Should I be flaunting my recent (graduated 2 years ago) Doctor-ness and success or fear that only gold diggers will flock? Or do I just take the gold diggers for what they are and enjoy sleeping with a bunch of them?

The biggest thing I'm struggling with is the endgame for TRP... I want a family, I want a wife and 2-3 kids and that whole shindig. I do not want to be some 40-something player who has a different girlfriend every year and 'lives it up' on my salary, just not for me. But with TRP stuff, how do you find a girl worth actually locking up (that isn't the aforementioned 'whore')???

Follow up: Do I need to be dating younger girls now (24-26) in hopes of finding girls a) before their wall and b) to find a future wife...