It's a hard question and there is no easy answer. I always suggest two good points:
1) Now is better than later. You will always be busier tomorrow whether you are talking about your personal or professional life. Never put something off until tomorrow if you can do it today.
2) Be present. When you have to juggle priorities, you want to make sure you give your full commitment to whatever you are focusing on. You will never be able to commit, if you are only half invested.
I am getting ready to do all of these things! I work full-time as a General Manager of a Verizon retail store. I am also a mom to three children under the age of 6, and married to my husband of almost 8 years. I got my bachelor's degree while juggling having my kiddos and getting my career started with this company. Therefore, when this opportunity to further my education came along, I was hesitant at first because I have already taken so much time away from them. But then I thought about it some more. If I can achieve my MBA, I can get promoted again quicker and have that time to put back into my family when the kids will have a better recognition of me being around, and can help shape their formative years. My husband is my godsend and without his love and support I would have struggled more with this decision, but for me, and for my family it was a no brainer. How I am going to be successful with this, it by having a schedule of events and ensuring that I'm staying on schedule with everything. A lot of my duties and tasks from my day-to-day can be delegated to my assistants in order to further their development and I can focus on my team to continue to challenge them and push them to get to their dreams and their goals with the company or outside the company in their personal lives. It takes a village and it takes dedication!
The best way I was able to manage gradschool, work, family and friendships was prioritizing what needed to be done first and what I could finish later; before or after work. Calendar or schedule dinners with friends and family so you know you have dedicated time for your social and family life as well. Keep balanced and make sure to go T your own pace. Life is a marathon, not a sprint so take your time and enjoy the journey!